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The sound was driving Katsuki out of his mind.
THUD. THUD. THUD.
Every hit echoed off the high ceiling of the gym like a drum. Katsuki sat on the wooden bench, a damp sweat towel clenched in his right fist, telling himself for the thousandth time that he was just resting between sets. He was just taking a breather. He wasn’t staring.
Except he’d been holding that same towel for thirty minutes.
His eyes were locked on Kirishima’s back, unable to pull away no matter how hard his brain screamed at him to look at literally anything else. The floor. The ceiling. The light fixture. The weights. Look at the damn wall, you idiot.
He couldn’t.
Kirishima wasn’t even wearing a shirt. Sweat slicked the redhead’s shoulder blades, trickling down the deep groove of his spine every time he shifted his weight to drive another brutal right hook into the heavy bag. With every hit, the muscles in his back flexed in a way that made Bakugo’s chest tighten so hard he forgot to breathe.
Why is my face so hot? Why does my throat feel dry? I’m just analyzing my classmate.
Pop.
A tiny, traitorous spark snapped from Bakugo’s left palm, singeing the corner of his towel. He flinched, digging his knuckles into his thighs to stop his hand from shaking. He was sweating, and his Quirk was reacting to it, and he couldn’t make it stop.
“Dude… how long has he been like that?”
The whisper came from a few yards away. Bakugo didn’t look, but he knew Sero’s stupid voice anywhere.
“Thirty minutes,” Kaminari whispered back. “He picked up that towel half an hour ago and hasn’t moved an inch.”
Katsuki’s jaw clenched so hard that his molars hurt. Shut up. Shut up.
“You know, Kirishima is ridiculously built,” Sero said casually, taking a sip of water.
“Oh, totally,” Kaminari chimed in, leaning against the wall. “Honestly, pity whoever has to block one of those hooks. Kirishima is looking extremely ripped today.”
Ripped.
They noticed too. Everyone is staring! Why am I looking at him?! I’m NOT looking at him!
A deafening BOOM erupted from Bakugo’s right palm, scorching the towel completely through, leaving a huge hole through its center and scattering hot sparks across the gym floor.
“SHUT THE HELL UP!” Katsuki roared, leaping off the bench so fast it screeched as it slammed backward across the floor.
“We didn’t even say anything to you!” Kaminari flinched, throwing his hands up in terror.
Katsuki didn’t care. His ears were ringing, his pulse was pounding in his throat, and his face felt like it was on fire. He had to make this stop before his brain melted out of his ears.
He stomped across the floor and marched straight into Kirishima’s personal space. Reaching out, he slammed his hand onto the heavy bag mid-swing, halting its momentum with a screeching rattle of the chains.
“HEY!” Katsuki barked. His voice hitched slightly. “That form is complete garbage!”
Kirishima stopped dead in his tracks. He blinked, wiping a layer of glistening sweat off his forehead with his forearm.
And then he smiled; that stupid, bright, toothy grin that made Katsuki’s stomach do a sickening, terrifying drop.
“Huh? Really?” Kirishima panted, wiping his neck. “I thought I was doing pretty well!”
Don’t look at his neck, especially not at the way his damp red hair curls at the nape of his neck. And don’t look at his chest. Absolutely do NOT look at his chest.
Katsuki pointed an accusing finger directly at Kirishima’s chest, but instantly pulled it back like he’d been burned, horrified by how close his fingers had come to Kirishima’s bare, heated skin.
“YOU’RE NOT!” Katsuki yelled, his palm sparking violently in the air between them. “Your rhythm is trash! You’re hitting a damn bah that doesn’t hit back!”
He spun on his heels toward the ring, dragging a hand through his hair in a sheer, desperate panic.
“Get on the mat! NOW! Before I blow you into the wall!”
“Hell yeah, Bakugo!” Kirishima’s voice boomed with genuine excitement behind him. “I was hoping you’d ask! I’ve been wanting to try out a new hardening move combo on someone who won’t hold back!”
Katsuki didn’t answer. He couldn’t. He walked toward the sparring mat with a rigid, heavy posture, feeling like he was marching towards his own execution.
He stepped onto the canvas mat and turned around. Kirishima was already unwrapping his hands, grinning up at him, unbothered, shirtless, and entirely too close.
Katsuki raised his hands, palms sparking wildly, praying to whatever god was listening that he didn’t accidentally blow himself up during the match.
The mat beneath Katsuki’s boots felt entirely too small.
Kirishima rolled his shoulders, his chest heaving as he caught his breath. Under the bright overhead gym lights, every single line of his abs, his shoulders, his waist was on full, agonizing display.
DON’T LOOK DOWN, Katsuki’s brain screamed, EYES UP. LOOK AT HIS CHIN. NO, NOT HIS LIPS, YOU DUMBASS. LOOK AT HIS HAIR.
“Aright, man!” Kirishima said, snapping his fists into a guard, his skin hardening across his forearms. “Give me everything you’ve got!”
He lunged.
It was supposed to go like usual, a fast right hook backed up with a blast to throw Kirishima off balance. But as Katsuki closed the distance, the heat radiating off Kirishima’s bare torso hit him hard. He hesitated for a microsecond as his eyes caught a bead of sweat sliding down Kirishima’s collarbone.
The distraction cost him everything.
Instead of landing a clean hit, Kirishima ducked under his arm, drove a shoulder into Katsuki’s midsection, and wrapped his arms around Katsuki’s waist to take him down.
Katsuki’s world violently tilted.
They hit the canvas hard, the impact knocking the air straight out of his lungs.
Before Katsuki could register the impact, Kirishima straddled his hips to pin his shoulders down. His calloused hands clamped around Katsuki’s wrists, pressing them flat against the mat.
He was sitting directly on top of him. He was shirtless, slick with sweat, breathing heavily, and looking down at Bakugo with a triumphant, beaming grin.
“You’re slipping up today!” Kirishima laughed, his face inches away from Katsuki’s.
Katsuki lay frozen; heat raced up his neck into his cheeks, flushing him a shade of bright, furious red that rivaled Kirishima’s hair. He opened his mouth to yell, to curse, to set off a deafening blast right in Kirishima’s face, but the words got caught in his throat.
Kirishima’s weight was solid over his thighs, his hands were hot against his skin, and the sharp scent of sweat and body wash was washing over Katsuki in dizzying waves.
He was going to die here. He was going to combust and die on the spot, and if this was how he went out, he’d probably end up telling Kirishima thank you.