Special thanks for Pinky102ZaneXd and @ryanconrad for helping me with this chapter! Rated T for the upcoming scenes lol. Later, I'll put some illustrations on some chapters :p

Credits: Prince belongs to Pinky102ZaneXd!!

Enjoy reading!

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"SANS?"

Sans paused, as he heard his little brother come out from the castle entrance. He was awfully sweating while recollecting his thoughts back from Snowdin Fields.

Sans tried to deny it, that kiss felt like a bliss, but now it was obvious. Not that he cared about Frisk anymore, all he wanted to do was to take her soul, get to the castle and let the reign of Dark end soon.

He'd be lying if he wants that to happen.

Thus, Sans was left to stew in his guilt and fear. His thoughts swimming around endlessly with knowledge that his careless actions had caused the person he loved the most so much pain. Too much, he never knew since when it started.

As well as the fact that what he'd done to try to fix it may have hurt her even more if she knew.

"MASTER ACCEPTED ME TO BE HIS APPRENTICE, WHICH I'LL BE STARTING SOON NEXT WEEK! I, THE GREAT AND NOBLE PAPYRUS, IS ON MY WAY TO MY DREAMS!!"

"that's good to know, then you should prepare your bottles and books, then."

"OF COURSE, I'M WELL PREPARED AND I KNEW THAT I'LL BE CHOSEN, I DON'T HAVE TO WORRY ABOUT PACKING UP MY THINGS. I'LL JUST HAVE TO PREPARE MY SPELLS TO SHOW MY GREATNESS TO EVERYONE!"

And with those words, with pure excitement and joy, Papyrus picked up his bone wand, waving through the air as he cast a spell,

"LET'S GO HOME NOW, BROTHER."

༻✧༺__________༻✧༺

The once loud and lively bar was now as quiet as it has been after 7 years had passed.

While she tried to focus her attention on reading one of the books, Grillby lent to her, Frisk's eyes kept wandering towards the cafe bar's door entrance. She was waiting for Sans's return. For his response.

"So, what was your name again, my dear?"

"Frisk."

She didn't expect the little spider monster to actually ask her name. When Sans told her about the RESETs, she was still confused how Toriel didn't recognize her.

"It's alright, my dear."

Muffet assured her. Well, that wasn't entirely true. After what Frisk did back from Sans' room, not to mention he did respond to it. But honestly will he still talk to her when he comes back.

"More importantly though," Muffet began, giving her a hot warm tea, "You don't have to worry about it, I think he likes it"

Frisk's back straightened in alarm. How did Muffet know? She was alone with Sans in the room, right?

"Wh ... What do you mean... he likes it?" Frisk said as she sipped her tea.

"Oh, I don't know." Muffet drawled while checking her customers' order list. "Because he seems to be that important about you. I wasn't expecting him to bring a human here. And that 'thing' I saw back there, guess you really do have something with that creepy prince."

"I don't know what you're talking about," Frisk edged, putting the cup on the saucer, "and he's not creepy."

Muffet clasped her hands in front of her in a pleading gesture and giggled. "If you say so. I'll go back to the kitchen, have fun, sweetie!"

Frisk gave a short nod in response, "See you" she said.

With that Muffet went to help Grillby with the orders and left Frisk sitting alone with her book. She proceeded to continue reading... and she let out a sigh.

Clutching the book to her chest, she worried her bottom lip with her teeth. Muffet might have had no way of knowing, in fact no one did as Frisk had taken great pains to disguise her growing affection for Sans, but after these years now she'd harbored very strong feelings towards him.

At first she wrote it off as a crush, an adolescent infatuation she would grow out of. But after they were free from Underground and as she grew, so did her attraction to him. Frisk couldn't help when he heard his voice, when she kissed him and in this situation it was a very bad idea.

Frisk came out of her musings, she smiled to herself...

"Maybe, I'll give it a try."

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Suddenly, two skeleton monsters caught her off guard, and with a yelp from one of the customer's bottle slipped from their fingers.

Sans and Papyrus stood in the doorway. They got back from the castle with the tall skeleton's teleportation spell. His older brother can teleport effortlessly without a bone wand and he's no match with Sans' skills of magic.

"BROTHER, I'LL GO TO THE KITCHEN TO COOK SOMETHING FOR US!"

"sure, paps."

"Sans!"

The short skeleton perked up in surprise while Papyrus went to the kitchen with Muffet and Grillby.

"what ya doin'... kid"

It's not safe to call her "lumen" in front of many monsters, Sans thought. They're in the headquarters and if someone knew outside he let a human with him, his plans would be ruined.

Frisk cheeks reddened. She wanted to smack herself. It may or may not have something to do with the kiss earlier.

Sans and Frisk stared at each other. It made small talk between them painfully awkward.

"Um, Sans?"

Sans realized dimly that he had been standing at the doorway a full minute without saying a word. He knew she'd spoken to him, but he was a bit too preoccupied to respond.

Warm and tingly didn't begin to cover it.

Say something you idiot!

"yeah, kid?" Sans managed, smiling brightly.

Perhaps too brightly as Frisk gave him a strange look. "A... Are you feeling alright, Sans?"

"Oh, yes," he cooed, his smile turning sultry. Everything in him suddenly felt loose and liquid. The hot, zinging buzz that had electrified his bones upon first seeing her had lessened to slow waves of heat rolling up and down his ribs.

Frisk studied him with a concerned look on her face. Sans realized he was staring again.

"Er, um, I mean, I'm fine, thank you." He cleared his throat and tried to ignore the sudden strong desire to lean into her and kiss those lips. They looked soft and he wondered how they'd feel against his once more. Clearing his throat, he tried to remember what he's gonna say.

Sans notices she's holding a book with her.

"you're reading something?"

Frisk looked down at the book clutched to her chest, "I... I am, Grillby, let me borrow some of his books."

"ah, yes, you seem really interested reading that," he shrugged and Frisk traced the ripple of his shoulders with her eyes. "i don't much care to read anything, but Grillby's books are truly fascinating."

"I'm sorry," she frowned. "About earlier, you know, um, that I kissed you."

"that's quite all right."

His smile, somewhere between an indolent smirk and a self-deprecating frown, made Frisk's stomach flip flop.

"sorry for leaving you all of a sudden earlier. i'll introduce you to the other monsters here in the headquarters so you'll get the hang of this place. Will that be alright with you, Frisk?"

"Sure."

Sans walked towards Frisk and sat beside her. She set Grillby's book on the table and busied herself by asking Muffet to fetch a chipped teapot, before retrieving two mismatched cups, saucers and spoons on the tea tray.

Frisk stole a glance at the short skeleton from underneath her lowered lashes. The bolt of electrified heat that raced down her spine. She looked away from him immediately.

Sans prepared the kettle and summoned his bone wand, muttering a spell to make a fountain of water shoot from the end of the wand. "i still wonder what happened at the last RESET."

"Me either." Frisk's thoughts are going fuzzy.

"how about those two?"

"Huh?" She found herself easily distracted.

"your sister and that kid-, I mean, um, Kris, do they know about the RESETs"

"I couldn't say that," she muttered.

Sans cocked his right brow ridge in question.

"I mean, no, I don't really know if they do." She hurried on, "Since I can only SAVE or RESET, so I don't think they have an idea about those or even the previous timelines."

"okay." His voice sounded queer, as if he wasn't sure which emotion to display. "i'll figure it out what happened and i still think someone is in control of this timeline, can be either with those two."

She surprised them both by reaching out to grasp his hand. "I'm sure you will, Sans."

A smile of genuine surprise and pleasure lit up his face. Their eyes locked and the look between them lengthened. Abruptly he realized he was staring and Frisk slowly let go of his hand.

"But first, can you help me find my sister, Chara. I don't know where she went and I think Kris is still out there, finding her by himself."

"oh, of course." was all he could say. When she didn't offer any more information on the matter he dropped it.

"Frisk, let's go to my room. there we could have our tea together." Frisk nods in response.

Her grip on her skirt tightened until her knuckles ached. What was she doing?

She should tell him.

She should.

She should simply open her mouth and tell him: That she has feelings for him, not just a friend. That she has loved him for a long time now. That kiss, does he feel the same as hers?

Frisk felt a bit drunk now even though she had tea. Intoxicated was a good word for it. Like champagne, she felt bubbly and light, no longer weighed down by indecision, embarrassment, or fear of rejection. All the things she usually felt around Sans since the day she realized her feelings towards him went beyond friendship.

Looking down at Grillby's book, she took a deep breath and tried to gather her scattered wits. What was she going to do?

Sans walked into the study adjourning his quarters. For years this room had sat empty and unused until Frisk fell in the Underground. Now it was a cozy abode filled with odd bits of furniture pilfered from various things she brought. She had spent many rainy afternoons curled up in one of the high backed chairs with a book and a cup of cocoa.

Their years of close friendship, not to mention their relationship created a veil of propriety that rendered their long hours together innocuous. No one paid any mind or thought it odd if the human spent the day sequestered in his study, or if the two of them took a day to the Shattered Falls.

Though it had taken some time, the king and queen trusted him implicitly with Frisk's well-being. In part, the unwavering trust of the royal Dreemurr family is what caused him to distance himself from her years ago. Everyone else trusted his judgment concerning her, but he was no longer certain he trusted himself.

Still, Frisk was his dearest friend and he couldn't bear to treat her poorly. He wouldn't turn away her company on account of a wayward infatuation on his part. He had no illusions about their stations in life, he simply feared making a complete fool of himself. Any fantastical notions of affection beyond friendship were just that, a fantasy.

Sans set the kettle by the fire, waving his bone wand, his dark turquoise witch outfit changed into a dark blue tunic, black trousers and leather boots. He scrubbed his hand over his tired face. He needed to get his emotions together.

With her magnanimous nature, Frisk sometimes did or said things beyond the societal norm of her position to help those she cared about. She was far more warm and caring than her sister, and he tried not to let his imagination run away with him. Though something about her today had him on edge. Frisk seemed ... not her usual self.

Sans was being silly, or perhaps wistful. Besides, what could possibly happen over a simple cup of tea?

"I guess, I can't really tell him. I shouldn't." Frisk mumbled to herself.

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The shriek of a whistling kettle broke Frisk out of her reverie. Lost in her own thoughts, she brought the tea tray into the study and set it down on the little table by the fire. Too restless to sit still she watched with hooded eyes as Sans moved about collecting cups, saucers, spoons, and the kettle. He prepared two cups of tea, one just the way she liked it.

When her heart started beating so fast? She wetted her lips with the tip of her tongue and tried to pick through the muddled tangle of sensible thoughts and insensible desires running rampant through her mind. No matter how she tried nothing would stick except the completely irresponsible inclination to tackle him on the worn settee.

Tackle him and do what? Her fevered mind asked. Her body answered with an obliging rush of warmth. By all the stars, she wanted ...

She wasn't entirely sure what she wanted, because she'd never, even in her wildest dreams, imagined her blood could boil like this.

But, she wanted to.

Frisk moved on impulse, standing closer to him than was proper, even for their close friendship. At that moment Sans turned, a cup of tea perched in his hand. Surprised to find her so close behind him, he jumped, sloshing hot tea down the front of him.

"oh, uhh, um." he muttered, setting down the empty cup and swiping ineffectively at his wet tunic.

"I'm so sorry," she said, sounding not very sorry at all. All of a sudden she felt very bold. "Let me help."

Frisk's hands pushed his own aside, feeling brief shocks of electricity where their fingers brushed. She deftly untied the sash of his tunic top before slipping her hands inside. They slid up his chest, pushing the thick material off his shoulders.

Sans started to feel the human touching him so freely. Despite a decade of growing closeness, propriety created a cocoon of modesty that society and station dictated neither of them intrude upon. Frisk had bestowed upon him the occasional affectionate caress, or hug, but Sans was bound by decorum and servitude to never initiate such contact.

This was the way of their lives, an ingrained system so embedded as to be above question. His surprise at a scant caress across his chest and shoulders was understandable and immediate. His widened eye sockets settled upon above her hair, the only part of her he could see from his vantage point. The heavy tunic top fell to the floor in an inelegant heap, and she set about undoing his turquoise cravat next.

"i don't believe my tie got any tea on it," he muttered, thoroughly out of his depth.

Frisk didn't hear him; she was entranced. Of course she had seen him without his hoodie or his witch outfit or his robes before, but she had certainly never helped him undress. She watched enthralled as she uncovered his bare neck bone.

Frisk leaned into him, closer than any friendly embrace. The sleek cap of her brown hair fitted nicely under his chin and her hastened breath ghosted over his bare collarbone. Indecision warred within her. She wanted to kiss him. Not a quick peck on the cheek, or a delicate brush of the lips. She wanted to kiss him fully and deeply on the mouth.

Sans' hands drifted up to gently cup her shoulders. Uncertainty was written in every line of his bones.

"Frisk?"

The slight tremor in his voice create a similar response in her body. Her hands moved before any slow-moving device like reason could follow, as if her skin craved all and any sensation. Even the brush of the slippery satin of his cravat made her fingertips tingle.

Tilting her chin up, she found him looking down upon her, his eye lights darkened with questions, uncertainties, and perhaps just a little hope. It was all the encouragement she needed to wind the loose ends of his tie around her hands, certain of what she intended to do, but still unconvinced it was a good idea.

Sans was momentarily stuck dumb by the way she was looking at him. He's certainly never seen such raw and open longing on her face, and never dreamed that she would look at him that way. She tipped her head back, using the grip on his tie for balance as she raised up on her tip toes.

He had just enough presence of mind to whisper, "what are you doing?" before her satiny mouth pressed against his own.

Physically it was the mere act of pressing their 'lips' together, but inside it was a cataclysm. A riot of new, wild emotions vied for her attention. Delight and pleasure warmed her, while anticipation built a fire in her core. At first his 'mouth' remained slack against hers until she tugged on the ends of his cravat, encouraging him.

Sans woke from his initial shock. He had a brief flash of reason, completely certain encouraging her was a very bad idea indeed. Viciously he trampled that voice down and gave himself over to the moment. Impatient desire curled through his bones, heightened to a frenzy by her unexpected actions. Her lips parted in shy invitation and she made a startlingly erotic noise of satisfaction when his tongue slipped into her mouth.

He groaned, completely shattered to find her taste as sweet and intoxicating as he'd imagined. He ravaged her willing mouth, expecting that this was his one and only chance to do so. Whatever trick of fate brought about this lapse in reasoning on her part, he would steal a few moments of pleasure before her better judgment caught up. Little did he know Frisk was disinclined to put a stop to his machinations. She swirled her tongue against his own, finding a graceful rhythm that left him breathless.

In her grasping quest to relieved the tension growing inside her, she pressed the full length of her body against his. Stretched so far up on her toes, she tipped forward, losing her balance and sending them both tumbling down upon the threadbare settee.

She wasted no time climbing onto his lap. Sans had a moment to consider that things were getting out of hand, but it was hard to remember why with her clad knees on either side of his hips. He slipped his hands around her waist, unsure if he intended to push her away or draw her closer. Before he could decide her mouth was upon his again, causing his thoughts to scatter.

Frisk felt alive and present, no second thoughts or worries about repercussions. Her hands roved over his shoulders and neck. They plunged into his skull, bringing his 'mouth' closer as she squirmed in his lap trying to assuage the hollow ache inside her.

His groan turned into a whine when her searching body found purchase on his stiff and growing arousal. One of his arms wrapped around her waist, while the other crooked up to curl his fingers over the back of her clothes. He leveraged both to pull her further down on his lap. They had one brief flash of blinding pleasure, punctuated by her surprised gasp, before he abruptly came to his senses.

One moment Frisk was incomprehensible, riding a wave of blistering sensation that brought promise of alleviating the needy ache building between her thighs, and in the next moment she found herself bereft of his warmth, dumped carelessly across the worn couch.

Sans strode across the length of the room trying to put physical distance between them. Frustration registered in every taught line of his long frame. He raked his hands through his skull, trying to gather his sanity. This tender blossoming of passion threatened to ignited into a wildfire if he didn't put a stop to it.

The tenuous thread of his control strained to breaking when he turned and saw the raw, erotic vision she portrayed among the old cushions. With rosy cheeks and swollen lips, her luminous eyes stared back, dazed and wanting. Her legs curled to the side. Abruptly he turned away, groaning in dismay.

"What's wrong?" she gasped, more than a little breathless.

He grasped the door frame, tempted to bash his forehead against it.

"what's wrong?"

His mirthless laughter was moderately hysterical.

"let's see, shall we. i've either completely lost all my faculties and am currently in the grip of a rather devious, albeit delightful, hallucination. or this is, in fact, reality and we've both lost our minds."

She blinked at him.

"this," he gestured between them, "cannot happen."

"Why not?" She climbed off the settee, approaching him. She was on fire and only he could help her quench it. She was in no mood to be dissuaded.

Not once in all his years had he ever felt intimidated by the young woman. She barely came up to his chin and was so slender he could fit his hands around her waist, but right now he felt stalked. He pushed his back against the door frame, clenching his fist to keep from touching her.

He took a fortifying breath. "kid-"

"Call me Lumen," she giggled, very close to him now.

He couldn't surmise what brought on this change of personality in her. Regardless, he ignored her request.

"i believe we both know nothing can happen between the two of us. we should go back to the bar since Papyrus gonna cook something for us and both forget any of this ever happened."

She looked up at him through her dark lashes. Her rosebud mouth puckered up in a pout and she batted her eyes at him. She could see Sans's resolve weakening and took the advantage to run her hands up his chest to toy with the buttons of his vest. She just needed to chip away at him until he broke. The short skeleton thought should have given her pause, but at the moment it only spurred her on.

"No one has to know," her voice was a sultry purr that surprised even her. She hadn't known this side of her existed.

"Just this once Sans, and then we can both walk away from here and act like nothing happened."

It was a seductive offer. Certainly more tempting than letting her leave him with an unfulfilled ache in his soul. But Frisk was someone special to him. Her sultry proposition tempted to the edge of depravity, but he held out against it.

"I didn't ask to be a Savior."

She didn't know where those words came from, or the conviction behind them, but more words followed in their wake, taking her by surprise.

"Someday I'll be expected to marry someone. I know Chara will let me choose who I like, maybe even someone I care for, but I can't choose whoever I like. I can't marry you for instance, even if I wanted to.

"I'm not saying I want us to be married," she added hastily, sensing she'd strayed too far from her original point. "I'm just asking, can't I choose this for myself?"

His hands itched to hold her and he swayed forward. "i understand what you're saying. truly, i do, but i cannot compromise you."

She'd been stealthily slipping the buttons of his vest free and came upon the last one. A naughty smile crinkled the corner of her mouth. "Who says you can't?"

"i say i can't."

He grasped her wrists, stopping her from working on the buttons of his shirt next. He hadn't expected to bare his soul to her today, but he found himself admitting the truth.

"i care about you too much to dishonor you this way."

She leaned forward, trapping their hands between them. The backs of his hands pressed against her breasts and she silently damned her thick combat clothes. A frown puckered her brow.

"Dishonor? How can it be dishonorable to be with someone who I care about, and who cares about me. You do care about me, don't you?"

"and they say there are no stupid questions."

His biting sarcasm was tempered by the look in his eye lights.

"i thought young woman like you were supposed to be chaste. didn't humans teach you that?"

She snorted indelicately. "You wouldn't say that if you knew half the humans in the Surface."

"you cannot be serious."

"I could tell you stories, you never struck me as the type to believe in fairy tales." she laughed.

"maybe not," his eyes looked a little sad, "but you did."

She didn't know how to respond to that so she chose to ignore it. Besides, she was tired of talking. Flattening her hands against his ribs. His grip on her wrists slackened as his head fell back. Her smiling lips ghosted over his neck bone, which bobbed up and down as he swallowed. She had to raise up on her tip toes again to reach the corner of his jaw bones. While she felt his hands slip around her hips to steady her.

"Please Sans," she pleaded.

His groan was of pure torment. For a moment she believed she'd won until he gently pushed her away.

"no."

Frisk blinked at him, uncomprehending for a moment. He used the delay to his advantage, moving out of her proximity. She followed him, trailing him like a pet unexpectedly spurred by a beloved master, confused and abandoned.

With as much aplomb as he could muster, he threw open the door and motioned for her to leave. He despised himself for the wounded look on her face, but it couldn't be helped. If she didn't leave here - now - he would likely be the cause of a very different brand of damage. A nasty voice inside his skull berated him for choosing today of all days to grow a conscience.

"i think it's best if you leave now." His formal courtesy was undercut by the pleading in his eye lights.

"please, Frisk."

Frisk knew she was hurting him, but she couldn't help it; She wanted him too much. And she could have him.

Sans softened in relief as Frisk approached, only to stiffen with dismay when she looked him straight in the eye and closed the door. If he expected her to persuade him, to plead or even beg, he was mistaken. She said not a word as she turned and went outside to join others in bar.

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"Frisk!" 

Kris shouted, concerned, he quickly hurried toward Frisk, but he's too late, Sans swiftly caught her before she could collapse to the ground, using his Bone Staff to teleport away from Kris.

He frowned as he checked that they were already gone, his eyes widening as he saw a large veins towards him. The veins had barely brushed him, yet Kris winced and managed a sharp intake of air. 

A strange man stood before him and smirked as a long of his green wavy hair, looping around his arm before placing both hands on his waist. He blinked his pink eyes down at the Kris.

"Why are you following, Prince Olen?" 

Kris stood straight, as he stares with his red eyes with a critical sneer.

 "Get out of my way." he demanded, his red eyes narrowing.

This man was Prince, one of the Royal Guards in the Underground . He was known for as the Nature's Wielder and thus much stronger than his sister, Diane; and for all intents and purposes, he was also more efficient at his job. He didn't show any weakness to anyone. He hardly even stayed around the other Royal Guards on some posts, because he found most of them annoying or stupid. 

Kris groaned in pain, holding his prism sword with his wounded left arm.

"And I never saw you around here." 

Kris was about to use his sword to attack, but he froze when he noticed that his feet were tangled with veins. 

"You didn't answer my question."

Kris decided against explaining and instead gathered enough strength to pull away from Prince's veins as he clumsily stumbled a meter away, standing in front of him. He held onto his sword for support. 

Kris took a deep, steady breath, glancing up toward Prince as he offered him a frustrated stare. His focus was solely on Frisk, and that thought Chara was also missing... he could hardly move, something with Prince's attack makes him to feel weak.

"Any time you'll be unconscious before I can have your answer and dispatch you."

Prince took a couple of step towards Kris, he talk less and its starting to get into his nerves. 

"Answer me, what's your purpose here in the Underground?"

Kris felt a little dizzy, "I...  I'm Kris..."

Before he could finish his sentence when a flashing red light started tugging him, Kris was already in Asriel's grasp as he stood beside with Chara. He sighed in exasperation before he lost consciousness, knowing that he finally found them, well they found him.

"He's with us and I guess, were supposed to go."  Chara said.

"Who said you could go with him, I'm not letting you until I can brought him to Undyne."

Chara and Prince holding their own weapons ready. 

"Prism, take him with you and meet me at the river, I'll see if their soul is worth than Toriel's."

Asriel nodded, holding an unconscious Kris, he summoned a glass portal behind him.

"I'll see you later... Chara." 

༻✧༺__________༻✧༺

(Next chapter; Chapter 5: Fallen Kingdom.)