It was Haechan's idea, technically.

"I can't focus on the floor today," he had said after lab, not quite looking at Mark. "Let's go somewhere else. Quiet-ish."

Mark had nodded like his heart wasn't suddenly tap dancing in his chest but because Haechan had just said quiet-ish like it was code for something else. "Sure. Quiet-ish. Specific."

Haechan had shrugged, eyes darting to the side like he was trying to seem casual and not like he had just asked Mark out on a not-date. "There's that café across the street."

"Yeah," Mark said. "Good light. Decent coffee. Risk of being poisoned by too much lavender syrup."

Haechan huffed a laugh. "You ordered that. No one made you."

Mark had grinned. "You judged me for it. Loudly. In public."

"That's because it was giving shampoo. The bad kind."

Now, an hour later, they were tucked into a corner table by the café's wide front window. The kind of table clearly meant for one person and a laptop, maybe a scone if you were pushing it. But they were sharing it anyway—shoulders hunched, laptops wedged precariously between cups and notebooks and a shared muffin they hadn't even discussed ordering. Mark had just split it and nudged half toward Haechan like it was the most natural thing in the world.

The café was warm in that cozy, slightly too intimate way. Golden lighting strung above them like fairy lights, quiet jazz humming from the speakers, the faint smell of cinnamon and espresso lingering in the air like a memory. Someone was typing rapidly nearby. Someone else was whisper-laughing into their phone. It felt like the kind of place where something could happen, if they let it.

They didn't.

But almost.

Every time Mark reached for his drink, his elbow brushed Haechan's. The first time, he had apologized. The second time, he hadn't. The third, it felt... intentional.

Haechan didn't say anything about it either. He just pulled out his notes and muttered, "Try not to spill anything on these."

"I'll do my best, but no promises," Mark said, unwrapping the muffin. "Some of us are clumsy and charming. It's my brand."

"You're not charming."

"Tell that to the barista who winked at me."

"That was at me."

"You wish."

Haechan shot him a look. The kind that wasn't quite annoyed. More like exasperated, with a secret smile curled in the corner of his mouth that he didn't quite let out.

After a beat, Haechan pulled a bag of snacks from his backpack and pushed it toward Mark. "I brought some snacks."

Mark raised an eyebrow. "You really came prepared, huh?"

Haechan shrugged, looking almost smug. "I figured you'd need something that wasn't just gummies this time."

"Very thoughtful," Mark said with a grin, grabbing a bag of chips. "You sure you're not trying to seduce me with snacks?"

Haechan rolled his eyes. "Mark. That's not even how that works."

Mark laughed, but it felt easy. Comfortable.

They started working. Headphones half in, laptops glowing, notes traded with occasional scribbles and comments. Every so often, Haechan would lean over to read something on Mark's screen, and Mark could smell his soap. Something clean and citrusy, like the soda he always bought. Too close. Too distracting.

It should've been productive.

It wasn't.

There was something in the air. Or maybe in Mark's chest. Or Haechan's eyes when he caught him looking.

The light hit Haechan's face just right. Hoodie sleeves rolled up, glasses sliding down his nose, hands wrapped around his coffee cup like it was the only thing tethering him to the moment. Mark tried not to notice how Haechan's fingers tapped the ceramic when he was thinking. Or how his tongue darted out to wet his lip before he whispered 3-Methylbutan-2-one under his breath like it was poetry.

"You're doing it again," Haechan said, still not looking up.

Mark blinked. "Doing what?"

"Staring."

"I was zoning out."

"You were zoning out at my face."

"It's a very symmetrical face. Can you blame me?"

Haechan shook his head and tried, really tried, to focus on his notes again. But Mark saw it. The way his ears went pink.

After a while, Haechan slid his laptop closer, shoulder now definitely brushing Mark's. "I need your brain for this part," he said, voice a little too soft.

"My brain is at your service," Mark replied, leaning in. Too much. On purpose.

They hovered like that, sharing oxygen, thoughts, glances. Ten minutes passed, though it felt like ten seconds and a thousand years all at once. Mark said something, he couldn't remember what, but it made Haechan laugh, and the sound was quiet, breathless, and entirely too much.

Then Haechan reached across to scroll on Mark's screen.

And his hand rested lightly, barely, on Mark's thigh.

It was nothing. Barely contact.

But Mark forgot how to breathe. Forgot how muscles worked. Forgot where he was, who he was, what the hell he'd been saying.

Haechan noticed immediately. His hand jolted away like he had touched a live wire. "Sorry," he mumbled, retreating behind his coffee like it was armor.

"It's fine," Mark said, voice hoarse. "Totally fine."

It wasn't fine.

It was whatever came after fine, when things had shifted just enough to be dangerous.

They didn't talk for a moment. Mark busied himself with his notes. Haechan stared at his coffee like it held answers to life's deepest questions.

Then, too fast, "You have foam on your lip."

Mark blinked. "Oh. Where?"

"Left side." Haechan hesitated, clearly debating whether to say more, and then he didn't say more. He reached out instead.

His thumb brushed the corner of Mark's mouth. Light. Precise. Like he had thought about doing it before.

It was a second.

Maybe less.

But everything stilled.

Mark's thoughts flatlined. His breath hitched. Haechan's thumb was warm and calloused and left a trail of static behind.

"You, um," Mark said, blinking rapidly. "Could've told me."

"You'd have licked it like a five-year-old," Haechan muttered, still not meeting his eyes.

"And you, what? Decided to use your thumb like a rom-com protagonist?"

Haechan stood so abruptly his chair scraped. "I'm getting a refill."

He left Mark sitting there, heart doing Olympic-level gymnastics, mind racing through thirty alternate universes where he grabbed Haechan's hand and said don't go.

Outside, the sky was turning gold.

Inside, something between them had shifted again. Just a notch.

Just enough.

And Mark wasn't sure if he could ever go back.

Sleep had not helped.

The next day was supposed to be normal.

That was the plan. Mark was a fan of plans. Haechan, even more so. Routine. Predictability. A schedule that hummed like clockwork and left no room for... whatever that was yesterday.

Which is why it was stupid. Deeply, annoyingly stupid. Because Mark kept thinking about it.

The touch. The thumb. The soft look on Haechan's face that hadn't meant anything but had felt like it did.

So when they met in the usual hallway before class, Mark was determined to act normal.

Which was going great until Haechan looked at him.

Just looked. With that same unreadable expression he always wore. Cool and calm and almost aloof. But this time, there was something flickering under it. Something twitchy. Something like regret or panic or God, why did I touch his face.

"Hey," Haechan said, voice low.

"Hey," Mark echoed, too quickly and way too loud. "So. Coffee."

Haechan blinked. "What?"

"I mean. Yesterday. Café. Coffee. It happened. It was good. The coffee. Solid beans. Strong roast. Mm." He made a vague sipping gesture, like he was auditioning for a toothpaste commercial.

Haechan's mouth twitched. "You okay?"

"Yup. Totally. You?"

Haechan hesitated. "Fine."

They stood there like two malfunctioning robots until someone jostled past them into the lab. Haechan cleared his throat. "Let's go. You're not gonna steal the centrifuge again, are you?"

"It was one time. And I didn't steal it. I... relocated it."

"To the other side of the room."

"Exactly. For science."

Haechan shook his head, that little almost-smile tugging at the corner of his mouth. He started walking, and Mark followed, trying not to stare at the way Haechan's fingers twitched against his side like he didn't know what to do with them.

Inside the lab, everything felt too bright. Too sterile. Not like the café with its warm lights and their dangerously close chairs and Haechan's fingers on his—

Nope. Don't go there.

They got to work. Mark focused hard on the beaker in front of him, pretending the smell of ethanol was enough to distract him from the fact that Haechan was standing half a foot away. Close enough that their arms brushed when they turned. Close enough that Mark could feel the heat radiating off his skin like static.

Haechan was being quiet. Not his usual sharp quiet. This was nervous quiet. Like he was thinking too hard. Like he didn't trust his mouth to behave.

They bumped elbows again, and this time neither of them apologized.

"You're being weird," Mark said eventually, too tired to keep dancing around it.

"I'm always weird," Haechan replied, eyes fixed on the test tubes.

"No, you're being... weirder."

Haechan inhaled sharply, then exhaled like it hurt. "I just..." He stopped. Looked at Mark. "I didn't mean to make things awkward."

Mark blinked. "You didn't."

Haechan raised a brow.

"Okay, fine. A little. But, like, a good awkward. Productive awkward?"

"That's not a thing."

"Sure it is. It's like tension. But sexy."

Haechan made a choking noise. "This is a lab. Stop saying sexy."

Mark grinned, triumphant. "You're blushing."

"I'm not."

"You are. It's very becoming. Keep going."

Haechan rolled his eyes, but it didn't have his usual bite. "You're impossible."

"And yet, here you are. Partnered with me. Touching my elbow every five seconds."

"That's your elbow."

"Still counts."

Haechan turned toward him slightly, leaning one hand on the table. Mark could feel the shift in air pressure. Like something was about to happen or almost happen and both of them knew it but refused to name it.

They hovered. Neither working. Not really.

And then Haechan, voice low—

"I think we're not very good at pretending nothing happened."

Mark's heart did something deeply illegal. "No. We're not."

"And I think," Haechan added, eyes flicking to Mark's lips before jerking back up, "if you keep making jokes about elbows and tension, I'm going to... say something dumb."

Mark's breath caught. "Try me."

Haechan opened his mouth. Closed it. Shook his head. "Later."

"Promise?"

Haechan's smile was small and dangerous and real. That was all the answer Mark needed.

Then Haechan shifted a little and pulled a bag of snacks from his backpack. He pushed it toward Mark. "I brought snacks. Figured you could use something to fuel your... creative genius."

Mark raised an eyebrow, amused. "You planning to feed me so I can work better?"

"Maybe," Haechan said, his grin almost sly. "You've been looking at the test tubes like you're about to sacrifice them to the gods of science."

Mark laughed and grabbed a snack. "And you're saving me from that fate. Very thoughtful. I'll eat your snacks in exchange for my undying gratitude."

Haechan didn't respond right away. His hand rested on the edge of the table, just slightly closer than normal. Mark could feel the pull of something else lingering between them.

They went back to their work. Kind of. Hands steady, hearts loud.

And if their shoulders stayed a little closer than necessary for the rest of the hour, no one said anything.

Not yet, anyway.