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There were a lot of things Kim Sunwoo could ignore.
His coach yelling at him about missed passes—tuned out. Group projects with his name slapped on them—someone else would fix it. Morning lectures—who even shows up to those anyway?
But Ji Changmin, sitting pretty on his lap in Sunwoo’s dorm room, talking animatedly about a 16th-century mathematician, while completely, entirely oblivious to what he was doing to Sunwoo?
Yeah. That he could not ignore.
“I mean, it's fascinating,” Changmin said, eyes sparkling behind his big round glasses. “Cardano was technically the first to publish the solution to the cubic equation, but del Ferro had discovered it earlier. There’s this huge debate in mathematical history about—”
“Changmin.”
Sunwoo’s voice came out lower than intended—rough, almost breathy. He shifted under the boy, trying very hard not to buckle from the way Changmin’s thighs were resting on either side of his lap. It should’ve been illegal for someone to be this distracting while being completely, criminally innocent.
“Yeah?” Changmin blinked down at him, tilting his head in that soft, wide-eyed way that made Sunwoo want to bite his lip off. “Are you listening?”
Oh, he was listening. Just not to Cardano.
Sunwoo exhaled slowly, throwing his head back against the couch. “Barely.”
Changmin pouted, shifting slightly. Slightly—but that was all it took. Sunwoo hissed, fingers digging into the armrest as the friction pressed against the very obvious, very real issue in his sweatpants.
“Sunwoo,” Changmin chided, completely missing the point, “You promised to be supportive of my academic passions.”
“And I am,” Sunwoo ground out, teeth clenched. “So supportive. Look at me. Being a… human seat for your genius ass.”
Changmin giggled, bouncing a little. Bouncing. Sunwoo whimpered internally.
“Oh no. You’re bored, aren’t you?” Changmin said, leaning forward as if he hadn’t just sent shockwaves down Sunwoo’s spine. “I can tell when you get that blank look on your face. Okay, okay, I’ll make it more interesting. So, there’s this theory that—”
“Changmin.”
This time it was almost a growl.
The nerd paused mid-ramble, blinking again. “Yeah?”
Sunwoo opened his eyes slowly and stared at him. Really stared. Changmin was perched on him like he belonged there—wearing one of those oversized pastel sweaters that fell off one shoulder, revealing a sharp collarbone, with slim jeans hugging the kind of thighs that had no business being on a guy who claimed he couldn’t even do a push-up.
His dark hair was messy from Sunwoo’s couch pillow. His lips were pink from chewing them in thought. His body—warm, light, and completely unaware—was currently trapping Sunwoo in hell.
“Sunwoo?” Changmin asked, confused, innocent, blinking at him again like he didn’t feel the thick tension crawling between them.
“Changmin. Baby. I don’t want to hear about cubic equations right now.”
Changmin flushed a little, lips parting. “O-Oh. Is it because you’re tired? Sorry, I know I ramble—”
“No,” Sunwoo cut in, voice tight. “It’s because you’re sitting on my dick.”
Changmin blinked. Then blinked again.
Then looked down.
“Oh.”
Silence.
“...Oh.”
Sunwoo bit the inside of his cheek to stop himself from laughing—or crying. “Yeah. ‘Oh’.”
Changmin’s entire face went red in slow-motion, like it was buffering. His hands flew up as if he was going to cover his cheeks but ended up flailing instead.
“I—Sunwoo—I didn’t—”
Sunwoo groaned, not from pain this time, but from how fucking cute this guy could be even while apologizing for causing a boner.
“I wasn’t trying to—oh my god—”
“You were talking about Cardano.”
“I like math!”
“And I like you, but baby, I’m dying here.”
Changmin looked like he was about to sink into the couch and disappear forever. He started to get up, clearly intending to escape, but Sunwoo’s hands locked around his waist in a flash.
“Where do you think you’re going?”
“I—I was gonna—let you—”
“You’re not going anywhere now,” Sunwoo muttered, pulling him back down until Changmin’s weight settled over him again, making them both freeze. “You sat down. You made your choice.”
Changmin whimpered. “I didn’t mean to—”
“Don’t care.”
Sunwoo leaned in, mouth brushing Changmin’s ear. “You think I would let you get away after making me rock hard?"
“Sunwoo!” Changmin hissed, half-scandalized. “I swear I wasn’t—”
“You show up with that little sweater,” Sunwoo murmured, dragging his hand up Changmin’s back slowly. “Climb into my lap like it’s your favorite place to be. And then you start talking about fucking Cardano while wriggling all over me like I’m a beanbag chair—”
“I wasn’t wriggling!”
“You were wriggling.”
“I was trying to explain the math!”
Sunwoo chuckled darkly. “Baby, if I wanted math, I’d go to class.”
Changmin opened his mouth, then closed it. His hands fidgeted in his lap, trying not to make eye contact, squirming again—which made Sunwoo groan again.
“I—I’m sorry,” he whispered. “I didn’t mean to…”
Sunwoo tilted his head. “You don’t have to be sorry. You just have to stop being so goddamn cute. It’s a problem.”
Changmin peeked up at him through his lashes. “Is it really… that bad?”
Sunwoo narrowed his eyes. “You’re still not doing anything about it.”
The nerd looked like he might combust on the spot.
“I—I can try?” Changmin offered weakly, clearly uncertain.
Sunwoo leaned back, smug and amused despite himself. “Oh? What happened to your theories and cubic equations, professor?”
“They’re less important right now,” Changmin mumbled.
“Damn right they are.”
The silence stretched.
Sunwoo’s hands slid slowly down Changmin’s hips, resting at the waistband of his jeans. “You want to help me out or what?”
Changmin bit his lip, looking more like a deer in headlights than a seducer, and yet—
He nodded.
Sunwoo’s brain short-circuited for a moment.
That soft, shy look paired with his nerdy voice whispering, “Okay…” like he was agreeing to solve an extra credit problem—it was too much.
He pulled Changmin flush against him, burying his face in the crook of the boy’s neck and letting out a low growl. “Fuck, I swear you’re gonna give me another boner before I can get over this one.”
“I didn’t mean to—”
Sunwoo kissed under his jaw “I don’t care.”