professor changbin x fem! student reader

part one of the yes series (see next chapter for part two)

word count: 9,903

content warnings: oral sex (m and f receiving), vaginal penetration, pussy job, fingering, overstimulation, unprotected sex, creampie (use protection kids!), professor kink, pet names (princess, angel, baby), light degradation (bin calls her a slut mostly), spanking with hand and a ruler, classroom sex.

let me know if i missed anything in this one-shot bc i tend to miss stuff! if you want to skip to the smut, scroll to the white heart divider!

Your first day of your last year of college was already off to a bad start.

Not only was it already eighty-eight degrees out at only ten in the morning, but you had tripped and fallen on your way out of your dorm, and skinned your knee. The cut still hurt like a bitch, even as you traipsed the fifteen minutes to your first class of the day.

And that was really the cherry on top of this miserable summer day. You had to attend your first and only college math class. And you were absolute shit at math.

If you had your way, you wouldn't be taking this course at all. Not only were you bad at the subject, but you hated it. You wanted to become a technical writer, which 90% of the time didn't actually require you to know any math. Writing? Love. Science? Fine. Even history was passable, Cs get degrees and all that. But math, for lack of better words, was the bane of your existence. You even struggled to pass back in high school.

So no one could blame you for putting off this class until practically the last second. You didn't want this to be your very last course before graduation, because that would be absolute torture. So you buckled in to take it your fall semester instead.

And oh how you were regretting it.

Now, you stood outside the classroom. The little window on the door was covered with white paper, so you couldn't see inside. If you could, you would probably have run away.

Instead, you steeled yourself, straightened your shoulders, took a deep breath, and pushed it open.

You had arrived a few minutes early, a little later than you usually were to other classes. You had admittedly stalled back at your dorm for as long as possible, knowing what was in store.

You took a seat in the second row, a few seats away from a quiet-looking guy with dark hair. You pulled a notebook and pencil out of your backpack, before looking up at the front of the room.

And that was when you saw him.

He was standing facing away from you, writing something on the chalkboard. He wasn't very tall, but he was incredibly built. His broad shoulders flexed in that navy blue button-up as he wrote, and you couldn't help but check him out. His movements were confident and sure, like he knew he belonged up there.

You'd never had a hot professor before. Maybe that was about to change.

Of course, he could have an unattractive face, you reminded yourself. Or even worse, a shitty personality. Just because he was ripped didn't mean he was hot.

Then, he turned around.

Dear God. Your heart rate picked up immediately, your chest contracting as you gazed upon him rapturously. You didn't want to look behind you to see if anyone else felt the same way. There was no way they didn't.

His dark hair was styled casually, wavy bangs sweeping across his forehead. He had kind, intelligent, yet humorous eyes, adorned with thick-framed black glasses, and small but full lips. Your eyes kept zeroing in on them, and you found yourself wondering what they would feel like against yours.

You shook your head, instantly clearing that thought from your mind. You could not be imagining your professor in that way. Even if he was young, maybe five years older than you at the most. You could not think about him like that. You were terrible enough at math as it was, and you couldn't afford to get distracted.

But when he smiled at the class, your mind went blank, forgetting your little pep talk. God, how could a man look so fine by simply existing?

"Good morning, class," he said, pointing up at the board. My name is-"

Seo Changbin.

You read the two words, written in a rushed, messy scrawl. You almost mouthed his name, wanting to feel what it was like to say it. But you kept your mouth shut.

"My name is Seo Changbin, and I'm your professor this semester," he continued. "This is a mid-level calculus class, so if that's not what you're here for, then you should probably leave now."

You inwardly sighed. Taking a mid-level math class when you hadn't taken math in four years seemed dangerous. And honestly, in any other situation, you might have hopped up and left, off to find the easiest possible course the school offered.

But how could you pass up the chance to be around this absolute specimen of a man for an entire semester?

So you stayed put.

"Good." Changbin moved his hair out of his face, and you watched with a fervor you never thought possible. If your friends could see you, they would call you a simp. For this man, hell yes you were.

"Now, I'll be coming around with the syllabus." He held up a stack of papers. "We'll go over it, and then jump into the first lesson. Don't worry, it's nothing crazy. Yet." He smirked, and your breath stuttered in your throat. Every time you assumed he couldn't get any hotter, he inevitably did.

He started making his way up and down the rows of students, handing them the small syllabus. He greeted a few who he must have known from a previous course, asking them how their summer was.

So he was an attentive teacher, too. Dammit.

Finally, he reached you. When your eyes met, just the hint of a smile graced those perfect lips. You held his gaze, unable to look away. Your entire body was on fire, and you crossed your legs in what you hoped was a casual manner.

For a split second, you could have sworn his eyes flicked up and down your body, once, checking you out. But it was so fast, you couldn't tell. Your face was so hot, you couldn't think straight.

"And what's your name?" he asked, coming to a stop in front of you.

As you introduced yourself, he took a step nearer, leaning down. He wasn't even that close, but you instantly felt the need to pull him to you. You weren't sure if he felt it too, but the energy between you was magnetic.

"Are you new here?" he asked curiously. "I've never seen you in my class before."

"No, I don't usually take math classes," you responded. "This is my first and only one, actually. I'm an English major, but it was required."

"So you're a senior?" he chuckled. "Waited till the last possible minute to join us, did you?"

You shrugged, embarrassment threatening to overwhelm you. But you didn't let it show, simply shrugging and smiling at him. "Math isn't my thing."

"Well, hopefully I can change that," he grinned, handing you a syllabus. "Welcome."

As he started class, you became enthralled with how knowledgeable he was. While most everything went over your head, you found yourself wanting to understand what he was saying. You wanted to impress him, wanted him to be proud of you. So while you would usually space out and succumb to boredom, you actually read the syllabus in its entirety, and took vigorous notes. Even if it was boring, you wanted to hear every word that came out of Changbin's mouth.

When class was over, and you were packing up, Changbin walked over to the desks, saying goodbye to some of the students. You ignored him, not wanting to come off as too eager.

"It was nice to meet you, Miss English Major," Changbin said, and you looked up, shocked that he remembered anything about you.

You glowered at him, rolling your eyes playfully. "Is that all you're going to refer to me as from now on?" you teased.

He shrugged, straightening his shirt and smiling. "Once I get to know you, I'm sure I'll refer to you as something else. For now, have a good day, Miss English Major."

——————————

Two weeks passed uneventfully.

Changbin's calculus class had started ramping up, and you were barely surviving. Everything was very confusing, and you found yourself blacking out for most of class just staring at your hot professor, instead of learning. All your other courses were a breeze, which left you tons of time to focus on failing to understand basic math.

You and Changbin had continued to talk, a little bit every day after class. He would ask you about your other courses, mostly about writing and all kinds of grammar. He seemed genuinely interested in you and your life, which was so opposite from any other teacher. He even wanted to know about your personal life, like your family and friends. You told him everything. Except the fact that your friends were dying to meet your aforementioned "hot professor". It felt nice knowing that he supported you, even if you were inevitably going to fail his class.

You fell into a nice groove, of sorts. You would act cool, funny, even effortless, to his face, and when you got back to your dorm, when none of your roommates were back yet, you would touch yourself to the thought of him. Fantasizing about his rough, strong hands holding your thighs open as he ate you out, or him caging you in between his huge arms as he pounded into you from behind. You couldn't help it, you were infatuated by him. You wanted him, no matter how terrible you were doing in his class.

All that changed on the Monday of your third week.

"Next week, we're having our first test," Changbin announced as he stood at the front of the room. He turned on the projector to display a PowerPoint presentation with information about the test.

It would be thirty percent of your overall grade. One test?? Thirty percent??

You felt your mouth hanging open as you stared up at the screen, then down at Changbin. How could such a kind, handsome man do this to you? Was he trying to make you fail?

Changbin met your eyes, and a smile graced his lips. You snapped your mouth shut, feeling your face warm. He definitely just saw you gaping at him like a fish. Totally smooth.

"I know some of you may be worried, and some of you may not," he said. "And if you're one of the former, I would love for you to stay after class and talk to me about it. I know you all have the ability to pass this test. Every answer to every question is in your notes. Study those as hard as you can, and you'll be more than fine."

You could feel your heart rate picking up as you thought back on the dozens of pages of notes you'd taken over the past four classes. You couldn't think of anything that made sense. How were you supposed to take a test and pass? Let alone one that was worth so much of your grade?

For the rest of the lecture, you could scarcely pay attention as you continued to spiral. Clearly, you should have just taken a different class, hot teacher be damned. To be fair, you hadn't expected the class to be this hard.

As the class ended, you started packing up in a daze. You had a morphology course - one of your favorites - next, but you were thinking about skipping it so you could study for this test instead. Even a week straight of studying probably wouldn't be enough for you to pass, so you needed all the time you could get.

You were so wrapped up in your thoughts that you didn't even notice someone calling your name, over and over again.

"Miss English Major! Miss!" Changbin finally called, and your head whipped around to face him, your cheeks warming at the nickname.

"I-sorry, what's up?" You stumbled over your words, trying not to look completely flustered. From his look of understanding, you knew you had failed.

"Would you like to study with me tonight?" he asked gently, approaching your desk.

"Ah, why would you think I need extra studying?" you asked quickly.

"I have eyes," he said with a quiet laugh. "And you look like you're about to pass out. Really, the test isn't going to be hard. But like I said earlier, I'm more than willing to tutor any student who needs help. I have the time."

You sighed. "Am I really that obvious? Or do I just look like an idiot?"

Changbin shrugged, moving so he stood in front of you. "I can tell you're really smart. You just don't believe in yourself. So... I'll see you at six tonight? I'll bring donuts?"

You relented, grinning. "If you bring glazed donuts, I'm in."

"Are there any other kinds?" he winked. "See you tonight."

Oh, you were so done for.

——————————

You arrived at 5:55pm, terrified of being late, or wasting Changbin's time. You assumed he was so busy already, and you didn't want him waiting on you.

Seeing as he wasn't there yet, you just stood awkwardly at the side of the room, unsure if you should pull up a seat by his desk, or just wait for him.

He arrived a few minutes later, carrying a cardboard box from the campus donut shop. Your heart leaped when you saw him, dressed in a casual black t-shirt, zip-up hoodie, and jeans. He would have fit right in as a student.

"Oh, you're already here." Changbin grinned at you, and your face heated. He was so hot when he smiled.

"I'm always on time," you pointed out.

"You're always late to my class," Changbin chuckled, shaking his head.

"Maybe it's because I don't like your class," you countered.

"Ouch." He came to sit at his desk. "Here, sit with me." He motioned to the chair next to his.

"So, what would you like more help with?" He asked when you got settled.

You sighed. "What don't I need help with?"

He frowned, tilting his head. "Am I really that bad of a teacher?"

"No!" you said hurriedly. "Math just really isn't my thing. I probably made a mistake taking a mid-level class. Everything is just really over my head. It's not your fault."

"Well, we can start from the beginning," Changbin conceded. He glanced down at your notebook, which was covered in your neat but hurried scrawl, and even a few shitty doodles at the top of each page. "May I?" he asked, pointing at them.

You nodded, pushing them towards him.

He took it, and flipped back to the beginning. "You've taken really thorough notes," he complimented, and you blushed. At least you were doing something right.

"I'm trying to pay attention to you." You smiled weakly.

Changbin started pointing at things in your notes, trying to explain them as thoroughly as possible. You had to admit, he was very good at dumbing down every concept, and even gave you examples of when they might be used in the real world. That tended to be your struggle with math. None of it made any practical sense, it was so abstract. At least with words, they always correlated to a real-world thing, or concept. Math was filled with what-ifs, and you hated that.

As he pointed at your notes, he moved closer and closer to you, his arm brushing yours. Your skin tingled from the touch, almost desperate to feel more of him. His arms were so firm, entirely made of muscle. Of course, you had known that from hours of staring at him. But being this close to him, getting to touch him, was intoxicating, making your mouth water. If only you could reach out and-

"Are you even listening to me?" Changbin's voice snapped you out of your lusting.

"Yes! I was just uhh..." you paused, unsure what to say.

He raised an eyebrow at you, pushing his glasses higher up his nose.

"Ah, no I wasn't. I'm sorry." You ducked your head, unable to meet his gaze.

He turned his chair to face yours. "I'm sorry, this is all probably way too much all at once. I should have realized that," he apologized. "Maybe we should take a five? Then we'll get back into it."

You brightened, nodding quickly. "Yeah, that would be great."

He grinned, sitting back in his chair. "You're nothing like my usual math students, you know."

You raised your brows at him. "That sounds like a badly veiled insult, Professor Seo."

His eyes darkened for a moment at the way you said his name, but he seemed to shake it off immediately. "No, it's just an observation. You're very different."

"How?" Your eyes drifted over to the box of donuts, which sat untouched next to you.

He shook his head at you. "Because of stuff like that. You're very easily distracted. Just have one, or I'll never get your attention back."

You smiled apologetically, before tearing the box open and grabbing a glazed donut. "I can't believe you actually brought these for me."

"For you??" Changbin exclaimed. "Nah, I wanted them. You were just an excuse. Pass one here."

You glared, taking a bite. "Okay that's rude. I would think you cared more about your struggling student." You handed him a donut.

He laughed at that before taking a bite too. "Of course I care about you."

You gazed into his eyes, watching the way his throat moved as he swallowed. Your eyes flickered back up to his, wondering if there might, just might, be a hidden meaning behind that.

Before you could stop yourself, or fully process what you were doing, you felt yourself moving imperceptibly closer to him, like there was an invisible force pulling you.

Your face was a mere foot away from his, your eyes remaining locked with his. "How else am I different from the others, Professor?"

He groaned, a low sound deep in his throat, and you saw a flame flicker to life in his eyes. A flame of desire, you wondered? Did he want you just as badly as you wanted him? Had he thought about you in the same way you thought about him? Your stomach twisted with desire, hot and potent.

Your hand reached out to grip his thigh, desperate to touch him. But before you could make contact, his hand grabbed your wrist, stopping you.

"What-" you began.

"We can't do this," he said. His voice was quiet, but firm.

"What are you...?" you trailed off, your heart thudding so hard your head hurt. Was he rejecting you right now? After that almost animalistic noise came from him, just by making eye contact? A noise that would most definitely be used to fuel your nightly desires? "But you were just flirting with me!"

"I was," he paused, licking his lips. You wanted to know what that tongue tasted like. "But I can't. You're my student, and it was incredibly unprofessional of me. I'm sorry."

You pulled your hand from his grip, moving your chair away from him, fighting to keep your voice steady. "Yes, you're right. Let's continue studying."

"Okay." Changbin nodded, picking up your notebook again. "Onto lesson two."

You continued the study session for another hour, before bidding him farewell. He promised that he would continue to help you study for two hours every night, and you agreed. He also demanded that you take the rest of the donuts home, but you refused. It felt wrong, somehow, to take something from him.

You walked back to your dorm, body burning with shame.

——————————

For the rest of the week, you dutifully attended each study session with Changbin, carefully avoiding any kind of physical closeness with him. You knew that if you got near him again, you wouldn't be able to control yourself.

Your thoughts were plagued by images of him. The way he smirked playfully at you when you got a question wrong, the glimmer of pride in his eyes when you got one right. His strong arms as he leaned over your notes, and his tight ass and muscular legs when he stood in front of the chalkboard to write every morning, or give lectures.

No matter how hard you tried to ignore your growing feelings for him, you couldn't help it. Every night, you found yourself desperately touching yourself to the thought of him doing unspeakable things to you, imagining it was him ravaging you instead of your vibrator. Him straddling you from above as he pounded into you with that thick cock, instead of your fingers. At this point, you knew it would never happen, but the forbidden, risky aspect turned you on even more.

Finally, the day of the test had arrived. Your heart had been racing with adrenaline. The night before, you had left this very classroom, saying goodnight to Changbin before cramming even more.

"Good luck, Miss." He'd smiled at you on your way out.

"Thanks, I'm really gonna need it," you had replied.

"No you don't," Changbin said as you left.

The test had been shockingly easy. You weren't sure if it was because Changbin purposely made the questions simpler than usual, or if his study sessions really had helped. But you whizzed through that test like never before. It gave you hope that maybe, just maybe, you weren't absolute shit at math after all.

Now, Changbin was passing out the test results. You hoped your gut instinct that you'd done well was right.

He placed the test on your desk, shooting you a faint smile.

"Well done, Miss English Major," he whispered, so quiet you could barely hear him.

You peeked at the top right corner, almost afraid of what it said.

92%.

Your head whipped around to face Changbin, who was now a couple of desks down.

Holy shit. Not only had you passed, but you passed with an A! How was that possible??

You wanted to run over to him and leap into his arms, but you had to hold yourself back. No one, including Changbin, wanted that.

You would wait until the end of class to celebrate.

As you packed up your bags, Changbin cleared his throat.

You looked up to see him motioning you towards him. Of course, you couldn't help but obey.

After the other students had left, you approached him, a huge smile plastered across your face.

"I passed!" you exclaimed, suddenly breathless. "I-I can't believe it! Thank you."

He shook his head, unable to hide his smile. "It was all you. You studied harder than I've ever seen any student do before. You earned it."

Before you could stop yourself, you wrapped your arms around his midsection and hugged him.

"Seriously, thank you," you said quietly. "I've never gotten an A on a math test, ever."

Changbin laughed, and for a split second you thought he was going to hug you back. His arms raised to grab your waist, and your heart thudded in anticipation. You had thought about what it would feel like to be in Changbin's arms countless times.

But instead, he pushed you away. His movements were gentle, respectful even, like he didn't want to hurt your feelings.

It did quite the opposite. It stung more to know that he wasn't an asshole who just wanted a girl's attention, but he thought he was doing the right thing in rejecting you for a second time.

"Well... thanks again," you said lamely, moving away from him. "I'll see you next week."

You practically ran out of the room, tears stinging your eyes. You wouldn't let yourself get hurt again.

——————————

Changbin stood at the front of his classroom, preparing for that day's lesson. It was two months into the semester, and about time for another test. The last one had been almost a month and a half ago, and his students were beginning to get complacent. It was his job to make sure they didn't get too comfortable.

It had also been about a month and a half since he'd properly talked to you. Ever since you had thanked him for all his help on that first math test, you had avoided him.

He wished you wouldn't. But you were right to. He would have done the same thing if roles were reversed.

He had rejected you, twice. Those glorious five days tutoring you were some of the best times he'd had in his entire three years as a professor. He'd never met someone half as bright, witty, or funny as you.

Or as beautiful.

Let's be real, fucking sexy.

That first day of class, when he'd turned around and met your gaze, still stuck with him. Those curious yet guarded eyes of yours instantly drew him in, and he'd had to inwardly slap himself just to focus on his job. He'd never let anyone distract him from work before, let alone one of his students. He'd worked hard to get where he was, and ever since he got the job, he'd made a promise to himself never to date a student. From watching his colleagues, it never ended well.

And no one had ever made him question that promise. Until you.

Everything about you intoxicated him. The way you rolled your eyes at his cringey jokes, that little crease in your left eyebrow when you were focusing extra hard, the dimple on your left cheek when you smiled. Your determination to be good at whatever you put your mind to. And something he hadn't expected: your desire to please him.

In a strictly professional sense, of course. Or so he convinced himself. Until you two had almost kissed. And he'd told you no. That had to be in the top five of his stupidest moments, and he had a lot of those.

For that whole week, he'd found himself wishing that you would try again. He couldn't stop thinking about you. When he went home to his empty apartment, he found solace in his hand, thoughts solely on you. About the way it would feel if it was your hand instead of his, gripping his shaft as you stroked him up and down, those nimble fingers knowing exactly where to place more pressure, where to be gentle. That pretty mouth of yours wrapped around him, taking his thick cock to the hilt. And he would cum to the thought of you, knowing that he couldn't have you.

Even when you hugged him after the test, he still rebuffed your advances. Why? What the hell was wrong with him? He wanted you, you wanted him. It was legal, you were both adults. And yet, he had still rejected you.

He still thought about you, obsessively so. The more he came to the fantasy of you, the more he became reliant on your presence, craved it, really. He looked forward to seeing you everyday in class, even if you didn't speak a word to, or barely looked at him. But your beautiful self walking to his class by yourself, gave him a sense of security.

Today, he arrived at class, eagerly awaiting your presence. When he turned around to face the door, slightly concerned because even two minutes into class, you hadn't arrived, his stomach quite literally dropped.

Because you weren't alone.

——————————

Hwang Hyunjin was the smoothest man alive.

You'd noticed him sitting a few seats away from you since the first day of class. He was incredibly smart, but tended to keep his mouth shut. He was always busy writing or drawing something on his notes instead of paying attention, and when you weren't busy staring at Changbin, you found yourself watching him instead.

The two of you had been paired up for a class discussion, and he mentioned that he loved art. Being the creative that you were, you asked him what he liked to draw, and he showed you some of the doodles he did during class. They were good, really good.

When he asked you out for coffee a month into the semester, you'd had no choice but to say yes. And you had a great time.

It was clear that Changbin had no interest in you, so who could blame you for wanting to spend time with another hot guy? Who cared if you still thought about him in the privacy of your dorm, late at night? That was just a phase. Every college girl had a crush on her professor at some point, right?

You and Hyunjin weren't really seeing each other, it was casual. So you had never come to class together, or showed any sign that you were interested in each other.

Until today.

Hyunjin had walked you to class, after treating you to coffee. You were even later than usual, but you found that you didn't mind.

But when you walked into the classroom, and Hyunjin suddenly grabbed your hand, it was clear that someone minded. They minded a hell of a lot.

Changbin's eyes seared into the two of you, his gaze roaming over both your and Hyunjin's faces, before landing on your connected hands. His jaw clenched and unclenched, a vein ticking in his forehead, but he stayed quiet. His fists were pulled tight at his sides, those huge arms flexing in a most mesmerizing way. You couldn't help but stare. Was there the potential that he was... jealous?

Of you. Being with another guy.

Before you could think about it further, Changbin cleared his throat, and Hyunjin sat next to you for the first time that semester.

You should feel giddy that this gorgeous man was sitting with you, but you couldn't pay attention to anything, except your stud of a professor glaring at Hyunjin like he wanted him to disappear.

"Today, we're going to be discussing next week's test," Changbin ground out, his teeth gritted so hard you could hear them scraping against one another. "Mister Hwang, do you remember what our first unit after last month's test was?"

Hyunjin paused next to you, brows furrowed. How was he supposed to remember what you'd learned over a month ago, off the top of his head?

"No Professor, I don't," he said evenly. "If I could just check my notes-"

"No, you may not," Changbin snarled, his eyes narrowed as he stared Hyunjin down. "Clearly, you weren't paying close enough attention."

"Professor!" you exclaimed, blood pounding. Why was he targeting Hyunjin all of a sudden? You thought he liked Hyunjin.

"What?" Changbin sneered. "Trying to protect your boyfriend?"

"Just don't." You rolled your eyes, looking away from him.

For the rest of the class, Changbin continued to pick on Hyunjin, calling on him for the hardest review questions, and actually laughing at him when he couldn't remember.

Finally, when class was over, the two of you made to leave.

"Miss, please stay behind," Changbin practically growled, gaze hot on your back.

"Will you be okay?" Hyunjin asked, glancing between the two of you.

You nodded. "Yeah, don't worry about me. I'll see you later."

Hyunjin followed the rest of the class out, casting one last look back at you.

🤍🤍🤍🤍🤍🤍

You stood behind your desk, staring at Changbin. He stared back at you, expression unreadable. Was he upset? Of course he was. He wasn't very good at hiding that during class.

He walked to the door and slammed it shut, the force startling you. But when he clicked the lock in place, your chest seized up. What was he doing?

"Come here." His voice was soft, yet you could hear him clearly. His face looked calm, but you could see the fire in his eyes as he gazed at you. Your breath caught in your throat as you wordlessly obeyed, coming to stand in front of him.

Was this really going to happen? Was he-

Before you could formulate a proper prediction, his lips were on yours. His hands fumbled at your waist with a desperation you didn't expect, even in your dirtiest fantasies. He picked you up, grabbing your ass roughly as his plush lips forced your mouth open, sucking and biting with enough pressure that would leave marks in the morning.

"Fuck, I've wanted to do this for so long," Changbin growled against you between kisses. Your hands slid into his hair, clinging to him as you kissed him back with equal strength.

"What took you so damn long?" you gasped, pressing your tongue into his mouth and rolling your hips against him.

He groaned, the sound low and guttural, before setting you on his desk as gently as he could. He slid a finger under your tank top strap, pushing it down slowly, his gaze devouring your skin rapturously.

"I've been so good, so in control," he breathed as if you were torturing him, his mouth coming to land against the shell of your ear. You shivered at the sensation. "Until today, when you decided to bring that poor Hwang boy along with you. What are you, boyfriend and girlfriend?"

You shook your head quickly. "N-no, it's casual," your voice shook despite yourself. "We've just been hanging out."

"You like that he's willing to give you attention when I wouldn't?" He leaned down, nipping at your shoulder and collarbone. "Has he fucked you?"

You moaned softly, closing your eyes. "No, of course not," you whispered. "And even if he had, why would you give a shit? I made a move on you, and you fucking rejected me, twice!"

Changbin let go of you, stepping back. For the first time, he looked embarrassed. Good, as he should.

"I'm sorry, Princess." He slid a hand down your arm, skating his fingers across your skin. "I thought I was making the right decision. But... I want you all to myself. Is that so bad?"

You glared at him. But no matter how long you tried to play hard to get, you knew damn well how this was going to end. You needed him too badly.

"Well, you better prove how much you want me, then."

His mouth curled into a smirk, and your core dampened at the sight. "I thought you'd never ask."

He pushed you back against his desk, shoving your legs apart, before tugging your denim shorts down your legs and ripping your panties clean in half.

"Changbin!" you gasped. Those were your nice panties, too.

"What? You won't be needing them," he smirked, holding them to his nose and inhaling a hungry breath, before tossing them away. "And from now on, you will call me Professor, not Changbin."

You gaped at him for a moment, before you realized he was watching you expectantly.

"Y-yes... Professor," you said weakly.

He smiled, kissing your cheek in an uncharacteristically tender way. "That's my good girl. Now I'll make you feel the best you've ever felt."

He traveled down the length of your body, pressing kisses to your bare thighs as he went, admiring every inch of you. Your breaths came in short gasps as you laid in anticipation. You didn't know much, but you were sure that Changbin was experienced when it came to sex.

As he gazed in appreciation at your soaked cunt, he tore his glasses off and set them on the desk, licking his lips. "Gonna need to get close and personal, huh Princess?"

Oh yeah, he was most definitely experienced.

But nothing could prepare you for the sensation of Changbin's tongue against your center. He pressed his mouth flat against your clit, swiping his tongue up and down in broad strokes. He covered your entire pussy with his warm, wet mouth before sucking and licking in earnest.

"Holy shit, yes," you gasped, your eyes widening as your hips jerked up against his movements.

He grabbed your waist to stop you, his tongue fucking in and out of your cunt as his lips pressed against the sensitive nerves above it. You moaned, your hand finding purchase in his hair as your vision sparked in and out, stars flashing before your eyes.

"Fuck, faster, please," you begged, tugging his hair as you tried to pull him closer.

"What's my name again, Princess?" he rasped against your core, his voice interrupted by his continued slurping.

"P-professor, please," you whimpered, gazing at him with wide, pleading eyes.

"Fuck, how could I say no to you, Princess," he snarled against you, yanking your legs open even further as his tongue moved impossibly faster, two of his fingers sliding into your pussy, adding even more squelching sounds to the mix.

The addition of his fingers nearly sent you spinning over the edge, your free hand gripping the side of his desk as your legs shook, your thighs trying to squeeze his head.

"Stay nice and spread for me, Angel," he sucked hard on your clit, and you sobbed his name over and over, clutching at him like your life depended on it, your entire body vibrating.

"Professor, I-I'm gonna cum, please let me cum!" you begged, squeezing your eyes shut as you ground your hips up against him, this time Changbin allowing you.

"Cum for me, Princess, let me hear you," Changbin ordered, pressing his tongue in just the right way against your throbbing pussy.

With a strangled cry, you rode out your orgasm against his mouth and fingers as he thrusted them in harder and harder, working you through your release as you crested the peak and came tumbling over, your whole body falling onto the desk in a trembling, sobbing mess.

"Was that good enough for you, Princess?" Changbin licked his lips as he gazed at you smugly, coming to his feet and gazing down at you.

You rolled your eyes, standing up to meet his eyes properly. "It was amazing, Professor," you murmured against his lips, before kissing him forcefully. The taste of you lingered on his lips.

He kissed you back hungrily, his fingers traveling back between your legs to rub your clit gently, his tongue slipping into your mouth. You licked his bottom lip, grinding against his fingers as you moaned into him.

"Let me return the favor," you whispered, pushing him against the desk this time, before kneeling in front of him.

"Let's just hope you're better with your mouth than you are at math," Changbin teased. But you could see the desire flaming in his gaze as he caressed your hair with a rough hand, fully pushing you down onto the floor.

"You don't have to worry about that, Professor," you said sweetly, and he groaned, eyes flickering shut.

"No more dawdling Angel, open up."

You unzipped his black work pants, tugging them down to his knees. Even with his dark gray boxers on, you could tell he was huge, and already hard. Pulling his underwear off, his cock sprang free, angry and red, leaking precum.

Your eyes widened, and Changbin kicked his pants to the side, smirking down at you.

"Big enough for you, Princess?"

"Perfect, Professor," you breathed, gripping the base with one hand.

"Ah shit," Changbin gritted his teeth, his hand already tangled in your hair. "Don't make me wait too long, Princess. I've already been waiting for months."

You giggled softly, sticking your tongue out and kitten licking the pretty pink tip. He was quite thick, so thick that your hand could barely fit around him. He was about seven inches long, with a pretty vein running along the right side. Your core throbbed at the sight, imagining how well he would fill you up.

"Fuck," he snarled, thrusting into your hand impatiently, a bead of precum dribbling onto your skin. "Are you asking me to punish you, Princess?"

You felt your core clench at his words, and you almost hoped he would just flip you over and spank you for disobeying him.

But that could happen later. Instead, you slid his entire length into your mouth, taking him so deep your nose hit his hips. Coarse brown hair tickled your face, and you shut your eyes.

"Holy-" Changbin choked out as you began sucking hard and fast, using your hand to rub the base where your mouth couldn't reach. Your saliva instantly became sloppy, running down his cock and onto his waist.

"Oh fuck yeah, just like that," he grunted, tugging your hair roughly as he thrust his hips against you, driving his cock further into your mouth. "I bet you just love being my little cockslut, don't you Princess? You like me using you like this."

"Mm," you moaned, sending vibrations up his cock. He shuddered at the sensation, his huge, muscular legs flexing next to you. One of your hands gripped his thigh, the other squeezing his taut ass as you fucked your mouth up and down on him so he didn't even have to move.

"Oh shit, you do know what you're doing, don't you, Slut?" He ran his hand through your hair, and you felt a tinge of pride shoot through you. A thin line of tears dotted your lash line and your jaw hurt, but you didn't care. He was impressed with you, and that was all that mattered.

"Only for you, Professor," you gasped as you took a quick breath, before sliding him back into your mouth. Your hands moved to cup his balls, and he growled, loud and animalistic, against you.

"Fuck Angel, you're such a good girl for your professor, aren't you?" he moaned, pulling your hair into two makeshift ponytails as he started fucking against you in earnest.

You started to choke on his harsh ministrations, but you didn't want him to stop. Your core was so wet, arousal was dripping onto the ground.

"I'm gonna cum, Princess," Changbin growled, as his hips stilled. "But I don't want to cum in your mouth. I want to breed that little pussy of yours. How does that sound?"

"I-it sounds amazing, Professor," you breathed as you pulled his rock-hard cock out of your mouth.

He grinned, yanking you into another bruising kiss. "That's my good little Cockslut," he murmured, picking you up and setting you back on the desk. "This is exactly how I imagined fucking you for the first time. You look so beautiful lying there, all wet and ready for me."

You whimpered softly, shooting a seductively innocent look at him.

"Fuck, do you know what you do to me, Angel?" He closed his eyes, his body trembling at the sight before him. "Even better than my imagination."

"You've thought about me, Professor?" you said faux-shyly, grabbing his hand and placing it against your core.

"Of course I have, Princess," Changbin chuckled, opening his eyes again as his fingers roamed over your clit gently. You shivered at his touch. "Who wouldn't think about ruining a perfect girl like you?"

"I'm not a virgin, Professor," you pointed out.

"I know, but you're perfect," he responded, stepping closer. "Just look at you."

"Professor?" you asked softly, gazing at him. "Can I ask just one thing?"

"Anything."

"Can you take your shirt off?"

Changbin's eyes flickered in amusement. "Do you like my body, Princess?"

You nodded vigorously. "I love your body. I think about it all the time."

"I like the sound of that," he murmured, leaning over and pressing harsh kisses against your neck. "What do you think about?"

"Fuck me, then I'll tell you," you breathed against him, starting to undo his shirt buttons.

He tugged the shirt over his head hurriedly, before coming to hover over you again, those perfect, muscular arms of your dreams caging you in. You whimpered at the sensation alone, pulling him closer to you so you could grab his cock, stroking him a few times.

"Fuck yes, Princess," Changbin choked out, before lining himself up outside of your core. "I need to be inside you right now."

"I need you inside me too, Professor," you begged, moving your hips back and forth against his hard cock, wet squelching sounds ensuing as his cock rubbed through your slit. You threw your head back at the overwhelming sensation, moaning into his shoulder.

"Fuck, you're gonna be the death of me," he pulled your face up and kissed you once. Then, screwing up his eyes, he slid his entire cock into you in one harsh thrust.

"O-oh shit!" you cried, eyes widening and hands coming to grab his broad shoulders. He filled you perfectly, his girth stretching you deliciously, that vein rubbing against your walls just right. "Fuck Professor, you feel so good inside me."

"God, you feel heavenly Princess," he croaked, his voice hoarse. "Can I move? Please, tell me I can move."

"Please move, now," you gasped, fingernails digging into his back. "Don't be gentle with me, Professor. I can take it."

"Yeah? We'll see about that, Angel." Before you could say anything else, he pulled all the way out, leaving you feeling incredibly empty, before thrusting back in with all his strength.

You squealed, fingers scrambling for purchase against him, as he pounded in and out of your tight, wet pussy over and over, filthy noises filling the classroom.

You whimpered against his neck, pressing harsh kisses against him as he thrusted in and out, balls slapping your pussy as he went harder and faster. His cock slammed against the spongy part inside of you, causing you to cry out and clench around him.

"Ah shit, Princess, ease up a bit!" he grunted, nipping your neck as his hips stuttered against yours.

"Y-you just feel so good," you sobbed. "Please fuck me harder, don't stop, please, Professor."

Changbin listened, continuing to hit that sensitive spot over and over again until you were a babbling mess, unable to say anything except "Professor".

"Fuck baby, can you stand?" Changbin demanded into your ear.

"Y-yes Professor," you breathed, and before you could stop him, he was carrying you over to the chalkboard, and setting you down, so your face was towards the board, ass presented to him.

"Well shit, don't you look like a treat," he whispered, slapping your ass with a calloused hand, before trapping you between his arms once more, his mouth against your neck.

You gasped at the stinging sensation of his hand against your skin, but it wasn't fully because of the pain. Him slapping you felt good. What did you have to do for him to do it again?

His fingers traveled between your legs again, feeling the dripping wetness that gathered there. You felt him smirk against you.

"Did my Princess like it when I spanked her? Does she like it when she gets punished?"

You nodded vigorously, closing your eyes. Was he going to think you were disgusting for liking something so violent?

Changbin started chuckling, and you glanced back at him. Did he find this funny?

"I might have underestimated you, Sweetheart," his hands traveled up to your breasts and squeezed, making you squeal. "I guess you were right. You're more of a whore than I thought."

"N-no Professor, I'm a good girl," you gasped, rubbing your ass against him as you begged for him to hit you again. "I just need you so bad, please."

"You want me to hit you again?" Changbin snickered. "Okay, I can hit you again. Anything for my princess."

He stepped away from you, leaving your skin cold. You missed his hulking presence warming you, his huge arms caging your body.

You watched with wide eyes as he stepped back to his desk and picked something up. What was he doing? He couldn't leave you hanging like this.

But when you saw what he had in his hand, you knew he very much was not leaving you hanging. He was just getting started.

"A ruler?" you said softly, staring at the wood strip in his hand. Your core pulsed at the sight, causing more arousal to slide down your thigh. Fuck, you wanted it.

"You said you wanted to get slapped, didn't you, Princess?" he challenged.

You nodded, trying to hide your desire. If Changbin saw how much you needed this, he might deny you.

"Yes, Professor," you responded, not moving from your position at the chalkboard.

"Good, Angel," he approached you with a satisfied grin on his face. "So, are you ready for your test?"

"Test?!" you squeaked. You hadn't expected that. You'd hoped he would just slap you with the ruler a few times, then fuck you silly.

"You're going to have a math test in a few weeks, aren't you?" He raised an eyebrow. "Don't you want me to tutor you still?"

You nodded furiously. You would fail without him.

"Well, consider this our first session." He came to stand behind you, running the ruler up and down your thigh a few times.

You shivered despite yourself. You would do anything he wanted at this point.

"So, answer this problem, Princess. The axes of two right circular cylinders of radius A intersect at a right angle. Find the volume of the solid of intersection of the cylinders."

You gasped at him, speechless. You had no idea what any of that meant. Solid of intersection? You were an English major, for god's sake!

"I-I don't know Professor!" you whispered, body quivering as you waited for his response.

Changbin tutted quietly, pacing back and forth behind you. You tried to watch him, but he kept going in and out of your line of sight.

"What a shame." His voice was dangerously low.

Suddenly, the ruler came slashing through the air, landing across the center of your ass. You let out a loud gasp, covering your mouth before you could curse or yell.

"Chang- Professor, what the hell?" you exclaimed, whipping around to face him.

"Did that stir up any potential answers?" Changbin said smoothly, ignoring your protest. "Please turn back around, Angel. We're not done yet."

You opened your mouth to argue, but you caught that steely look in his eyes, and obeyed.

"Well?" he prompted. "Anything?"

"N-no, Professor," you said meekly. "We haven't learned anything half that difficult yet."

This time, as the ruler made contact with your ass again, you were prepared. You bit your lip so hard it almost drew blood, but you had to admit, it felt... nice. The stinging sensation it left after the pain was gone was incredible.

"Fine, if you can't come up with even a guess, how about this. What is the mathematical perception of the gradient said to be?"

You paused, thinking the question over. You knew Changbin had talked about this in a lesson at some point, but it had been a while ago...

"Is it tangent?" you said with a little smile. You knew the answer was wrong but... you also didn't mind.

"I'm sorry, Princess," Changbin grinned, and the stinging pain of the ruler raced across your skin.

You let out a stifled moan, squeezing your eyes shut as hard as you could. Oh god, did Changbin hear that? He was going to think you were such a whore.

Changbin set the ruler down on his desk and slid a hand around your waist, breaths coming hard and fast against your neck. You whimpered softly, unable to look back at him.

"I knew you liked that, you little Pain Slut," he snarled into your ear, nipping the lobe. "You're my little Pain Slut, aren't you?"

"Y-yes, only yours!" you exclaimed. "P-please Professor, fuck me again."

"Mm, you're just insatiable aren't you?" he snickered, his hand coming down onto your ass cheek, sharp and hard. "Now say thank you, Professor."

You cried out, your core soaking wet. "Th-thank you Professor!" You forced out through the blinding pleasure.

His hand came down on your other cheek. "Again."

"Thank you, Professor!" you moaned, turning your face to him and pressing your lips against his.

He didn't pull away, as the hand he used to spank you wound around your leg, lifting it up so your body was still facing the chalkboard, but your lips were attached to his.

"I'm gonna fuck you like this now, Angel, down and dirty. I'll bet you like it like this, don't you? Seducing your poor professor, and letting him have his way with you in his classroom. That's exactly what you wanted, wasn't it?"

"No, I didn't mean to seduce you," you mumbled against his mouth, as he positioned his hard, heavy cock outside your entrance. "You're just so hot and smart, and I wanted you so bad. But you kept rejecting me so I gave up, remember?"

"How do I know that little boyfriend wasn't just part of your plan to get me to change my mind?" Changbin challenged, finally breaking the kiss.

"Well, if it was, it worked, didn't it?" You teased him. "Now are you going to fuck me or not?"

Changbin growled deep in his throat, thrusting his hips slowly against you, running his cock through your wet folds. "I'll fuck you when I'm ready to fuck you, Princess. Not sure you deserve it, with all the stunts you've pulled. And you didn't even get that easy math problem right."

You giggled softly. "If I get it right, will you fuck me properly? Nice and rough?"

He paused, like he was pondering the question. "Sure, Angel. What's the right answer?"

You turned around, pressing your lips against his ear gently. You watched in satisfaction as he shivered. Thank god he was holding your leg up, or you would be numb by now. "It's the slope," you whispered to him, lips curling in a smile. You knew you were right.

"Mm, you knew the right answer the whole time, didnt you, Slut?" Changbin shook his head at you, a hungry glint in his eyes. "But you were a good girl, listening to your Professor so well. So I guess you get a reward."

"Yes please, Professor." You immediately started begging at the prospect of his cock inside of you. "Please fuck me now."

"It takes a lot of self control to stay away from you," Changbin groaned. "Self control that I clearly do not have."

This time, he thrusted into you nice and slow, one inch at a time. You gasped loudly as he shoved you up against the chalkboard, still holding your leg up, as he began pounding in and out of you mercilessly.

"Fuck, this pussy was made for me, Angel," he hissed into your hair, breathing deeply as he did so. "So tight and wet, squeezing me perfectly. You hear that? This pussy is all mine."

"Yes, it's all yours," you wailed, fucking your hips back against his, forcing his cock to impale you to the hilt. "You feel so good inside of me, Professor."

"Mm, hell yeah I do baby." His huge arm wrapped all the way around your waist, trapping you entirely as he hammered in and out, the lewd sounds of his length thrusting turning you on even more.

"Fuck, Professor please touch me!" you begged, grabbing his arm that was holding your leg up and sliding it towards your clit.

"You're such a greedy little girl, aren't you?" he sneered, pressing rough kisses up and down your collarbone, sucking harsh bruises along your soft skin. "I can't deny you though, can I?"

His fingers slid over your sensitive nerves and rubbed in rushed, frantic circles as his hips pounded against yours, causing the entire chalkboard to shake and rattle.

"O-oh yes Professor just like that," you panted, your legs nearly failing as he turned your entire body to jelly.

"Don't give up on me now, Princess," Changbin warned as he spun you around and picked you up, not removing his cock from your throbbing pussy. "You don't cum until I do, you hear?"

"Of course, Professor," you whimpered helplessly, the new position hitting spots inside of you you hadn't known even existed. "Please go harder!"

"Just for you, baby," Changbin ground out, and he started bouncing you up and down on his huge length.

The vein on his cock slid against your nerves addictively as you wrapped your shaking legs around his waist, clinging to his beefy arms desperately. Your core throbbed as you tried to be a good girl and hold your orgasm back, but it was coming.

"Please Professor, let me cum!" you pleaded, pressing kisses up and down his huge pecs, sobbing into his chest. "I'm so close, I've been so good!"

Changbin grunted against you as he bullied his cock deeper and deeper into your cunt, hitting your g-spot over and over while you pleaded incoherently to please, please let you cum.

"Shit, okay, cum for me baby," he hissed.

You didn't need to be asked twice. Your hips shook against him so violently you thought you were going to pass out. Stars blinked in and out of your vision as you cried, "Professor, please!" once, your pussy clenching around his cock like a vice, as he pounded his cock infinitely faster. His fingers pressed against your clit, and you were done for. You exploded around him in a puddle of whimpers and moans, clutching onto him for dear life.

"Holy shit baby, you're so fucking hot," Changbin panted, squeezing his eyes shut, his thrusts becoming more jerky and unstable. "I'm so fuckin' close, Princess, gonna cum inside that slutty little pussy of yours, yeah?"

"Oh fuck, please give me your cum Professor!" you begged, moving your hips in time with his. "Want you to breed me like the good girl I am!"

"Fuck Angel, you really want it?" Changbin hissed, his hips stuttering as his lips smashed up against yours again. "You wanna feel my hot cum inside you?"

"Yes Professor, please, I need it," you breathed against his mouth, biting his bottom lip and sucking it into your mouth.

Changbin thrusted sloppily in and out a few more times, his breaths stilted and hoarse, before halting entirely inside of you. You felt his warm cum fill your pussy, ropes and ropes of hot, sticky liquid, and you let out a shaky moan, closing your eyes at the sensation.

As he was about to put you down and pull out, you shook your head, gripping his arms.

"P-please, stay inside." Your legs tightened around his waist. His softening cock felt so good, keeping his warm cum inside you. You didn't want him to let go, not yet.

"You like me cockwarming you, Princess?" Changbin's cock stiffened at your actions, and you nodded.

"You feel so good inside of me," you sighed, running a hand through his hair.

"I bet I do," he said cockily, and you slapped his arm.

"Way to ruin the moment, Changbin," you glared.

He laughed, finally letting go of you and setting you back on the ground.

"I'm kidding, baby." He pressed his lips against yours, much more tender this time. You melted against him, wrapping your arms around his neck and pulling him close.

"I like the confidence." You giggled against his lips, before breaking apart. "I should probably go. I've got another class in an hour, and I don't want to walk in looking like this."

"I wouldn't want that either," Changbin observed. "You might get dress-coded. Or arrested."

When you were both dressed and semi-cleaned up, you waved goodbye to Changbin.

Changbin waved back, a little smirk on that handsome face of his.

"So, we on for another study session tonight?"

You smirked, biting your bottom lip before replying:

"Yes, Professor."

laska's note —
wow, this one shot took me forever to finally finish! but i wanted it to be perfect you y'all, so i spent a long time figuring out the plot and exactly how i wanted everything to go. i really hope you enjoyed it, because i'm kinda proud of how this turned out. i'm sorry for the slow ass updates, but again it's just supposed to be for fun! hopefully i'll get some more content out soon. leave any comments about what you liked, i love reading them! until next time... 😏💋