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It Started with a Prank

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Bakugou Katsuki was extremely successful for a twenty-two-year-old pro hero. He had his own agency, worked with his best friend/crush, and had fifteen interns and ten sidekicks. In all, he’d done well for himself in the four years since graduating UA. He’d finally broken the top fifteen heroes the previous month, and he was still climbing. Being the number thirteen hero at twenty-two wasn’t awful. Of course he wanted to be number one still, and he’d get there, but for now, he was fairly happy.

As he strode into the locker room to change out of his costume, he frowned. It was quiet. Too fucking quiet.

Even this late in the day, there were normally a few people joking around or showering or chatting, but his footfalls echoed heavily against the locker room walls as he headed toward his personal locker.

Katsuki’s jaw clenched, and he glowered at the silence, daring it to fight him.

Something rustled across the room, and he sneered at the sound before heading toward it. Katsuki was a large man. He had broad shoulders and thick muscles. He’d grown a lot since his days at UA, and thanks to his quirk, moving quietly wasn’t normally something he concerned himself with.

This, though, required stealth. It required cunning. It--


The slap on his arm was followed by a giggle, and Katsuki shoved the person away. “The fuck is wrong with you?”

Teniki Michi laughed as he stumbled backward, arms crossed over his gut. He was a tall, lanky man with short black hair and brilliant green eyes. His quirk was pretty unusual: He could swap people’s genders temporarily. The swap usually resulted in the affected person’s quirk changing slightly, too, which made it harder for villains to escape, since they didn’t have time to adjust to the changes. 

“S-sorry, boss! I had to, though! Chargebolt dared me!”

“He fucking what? ” he snarled.

“Dared me to change the gender of the first person who walked in!”

Katsuki was about two seconds from blowing the idiot up when his words sank in and he realized he was shorter than he used to be. He lifted his hand. The fingers were slim and feminine, still covered in callouses and a little knotted from the hard work he’d put into training, but they were smaller than usual.

He was smaller than usual.

Katsuki whirled around and bellowed, “YOU’RE FIRED!”

“Aw, c’mon, man! It’s just a prank! Look, you’ll be back to normal by the morning, okay?”


Michi frowned at him. “Dude, it’s just a prank!”

“NO!” he roared. “You used your quirk on another hero without an actual fucking reason. Get the fuck out of my agency, you piece of shit!”

The tall man’s expression fell. “You can’t be serious!”

“Do I fucking look like I’m joking?” he seethed. “Clear your shit out and leave.”

Michi looked at a complete loss. He was one of Katsuki’s interns, and he worked directly under Kaminari, but fuck, if this was how the blonde moron was training his interns, then he needed a serious fucking lecture.

“Get. Out.”

The man bowed his head in shame, but headed to his locker to collect his things. It didn’t take him long, but he dragged the whole affair out, like he was hoping that Katsuki would change his mind.

When it was clear he wasn’t going to, Michi finally left, the door to the locker room swinging shut behind him.

Katsuki seethed in silence as he paced, trying to figure out how his quirk had been altered. He tried to spark his palms, but nothing happened. Tried to sweat, but it didn’t work on command like normal. The alteration was enough to throw him off his game, which meant he couldn’t be on-call until he was back to normal. It meant he couldn’t help out if a major incident took place, which meant his rank could drop in the next few hours.

He was furious. Even more annoying, his uniform kept slipping off. Finally, with a muttered threat about how he was going to fire the shit out of Kaminari, he stalked back over to his locker and stripped out of his costume.

The door to the locker room opened, and he heard familiar, too-happy whistling.

Katsuki’s shoulders tensed. He was all but fucking naked, and Kirishima had just walked into the room. His locker was right next to Katsuki’s, too; he’d made sure of it when he’d put the agency together. See, Kirishima wasn’t just his second in command: Katsuki had had a crush on him since their first year at UA; he’d just never said anything. For one, he was pretty fucking sure Kirishima was straight, and two, Katsuki had forced himself to focus on graduating and training before everything else.

That included relationships.

He frowned as he looked down at his body, gears turning as he tried to think about how to hide his very female body. Then, something inside clicked.

He was a woman.

Temporarily, yes, but the fact remained: He was a woman. He was a woman, and Kirishima was straight. Kirishima was straight, and Katsuki was into him, and--

The redhead rounded the corner and stopped, eyes wide and a fierce blush blooming up his neck and over his cheeks.

“Oh. Um… h-hey, I think you might be in the, uh… wrong… wrong room,” Kirishima said, hand shyly covering his eyes about halfway through the sentence as he turned away. “A-are you new, or…?”

“Fucking… it’s me, shitty hair,” he snapped, shoving aside his previous thoughts. “Changetastic thought it’d be a funny idea to slap me with his goddamn quirk.”

Kirishima gave a nervous laugh, then stopped. “Wait, what?”

Katsuki grumbled, “I’ll be a dude again in the morning.” He frowned down at his naked legs and bare chest. He was still wearing his boxers. At least one thing still sort of fit. They were a little tight around his wider hips, but whatever. He’d take what he could get. “He’s fucking fired, though.”

The redhead nodded, still hiding his face behind his hand. “Ah. Yeah, p-probably a good idea. Can’t have… um, have your interns going around using their quirks on each other.”

“Yeah,” he grumbled, crossing his arms over his chest. “Oi, you got those stupid wraps you use for your arms still?”

“Yeah, man. Why?”

Katsuki uncrossed his arms and stared down at his heavy tits. “Kinda need something to hold these things up.”

“What things?”

“Stop hiding behind your fucking hand,” he snapped, annoyed.

Kirishima wasn’t generally shy in the locker room. He turned red if he caught sight of Katsuki nude, but he’d never acted like this before.

“I just, um… you’re a chick now, and it’s a bit unmanly to stare.”

Katsuki rolled his eyes. “Just come open your goddamn locker, dumbass.”

Kirishima edged toward him, still trying not to look, and it was pissing Katsuki off. He was about point-two seconds from slamming the other man against the lockers and just making him look when the redhead tripped over the edge of the long bench that ran down the center of the room. He landed hard with a grunt.

The blonde ground his teeth together before walking over as Kirishima rolled onto his back. He glared down at the redhead, who blinked up at him, cheeks bright red.

“Oh, um… I…”

Enough was enough.

Katsuki plopped down onto Eijirou’s stomach and leaned forward, eyes narrowed. His arms were still crossed over his chest. “You’re a fucking idiot.”

“Ah, um… K-Katsuki? Dude, you’re, uh…” His voice cracked a little, and the blonde smirked as he realized just how much power he suddenly had.

“I’m what? ” he asked, shifting backward a little and feeling Kirishima’s hard dick pressing against his ass. “I asked for your fucking help. So, what? Gonna just lie here and be a useless, blushing mess, or you gonna actually help me?”

He cleared his throat and tried to speak before looking away. “Um, dude, I… l-look, maybe, um… shit.” He groaned when Katsuki rolled his hips back, head thunking back against the cement as his eyes slid shut.

Katsuki smirked and rolled his hips again, letting his new clothed pussy rub over the hard bulge in Kirishima’s pants. A spark of pleasure darted through him. Shit, that feels good. “Yeah? Like that?”

“D-dude,” he rasped out. “N-not that I’m not, like, totally into this, b-but… um…”

Katsuki moved again, breaking Kirishima’s train of thought.

“Holy fuck, that feels so good.”

He hummed and leaned closer, inhaling the smell of Kirishima’s body spray. The slight tang of sweat peeked through, and he smirked. “Yeah? Like that?”

Large hands rested on Katsuki’s hips, stopping him from moving again. Red eyes opened, though his pupils were blown with lust. “Why… why now?”

Katsuki snorted. “Eh? Stupid question. You’re straight. I’m a chick.”

“Um… bro, I’m not straight.”


Kirishima laughed nervously. “I’m pansexual. I, uh… gender doesn’t matter to me.” He forced a grin, though he licked his lips as his gaze darted to Katsuki’s heavy, pale tits before returning to his face. “Wait, does this mean you… you like me?”

It was Katsuki’s turn to blush. He shoved backward, crossing his arms over his chest and glaring at the lockers to their left.

The redhead sat up slowly, causing Katsuki to slip onto his lap. He grunted when Katsuki’s weight shifted to his erection. “Fuck.” Then, a little firmer, “Bro? Did… did you think I’d only like you if you were a girl?”

He wasn’t gonna cry. He fucking wasn’t. Katsuki scrubbed his eyes and snapped, “How the fuck was I supposed to know, hah?”

“Dude,” Kirishima reached up and wiped his tears away. “I like you. I’ve… liked you for a long time, Bakugou. Girl or boy--it doesn’t matter to me. I like you for you.”

“Sap,” he muttered, trying to ignore how much those words made his heart swell.

He beamed and leaned in, bumping their foreheads together. “Does this mean you like me, too?”

“Shut up.”

That earned him a warm, full laugh. “Oh my gosh!” Thick, muscular arms wrapped around Katsuki’s shoulders, and Kirishima pulled him close, kissing his cheek before almost instantly pulling back. “Oh, sorry. I, um… you have no idea how much--”

He clicked his tongue against his teeth. “Yeah, I fuckin’ do.”

“Can we… I… I wanna…”

Katsuki rolled his eyes and closed the gap between them, pressing his lips to Kirishima’s.

The redhead was practically vibrating with excitement, his hands sliding up Katsuki’s arms and to his shoulders. One slipped around and wound through his short, wild hair. His fingers knotted in the spiky tresses.

Their tongues rubbed against each other, desperate and wild, and when Kirishima pulled on Katsuki’s hair, the blonde gasped into the other man’s mouth.

Kirishima moaned and pulled back, breaking the kiss. “Bakugou, holy shit.”

“Katsuki,” he mumbled. “Just… call me Katsuki.”

“Eijirou,” he replied with a wide, hopeful smile. “I wanna kiss you more, Katsuki. Can I?”

He eyed the other man. It wasn’t like he needed reassurance that the two of them were gonna stay together after this or anything, but…

He’d take what he could.

“Don’t be fucking stupid.”

The other man looked confused. “Oh.”

Katsuki closed the gap between them, kissing Eijirou stupid. Well, stupider. When their lips parted, he murmured, “I want you to wreck me, Eijirou.”

A gasp broke through plush lips. “You… do?”

“Ain’t gonna have this body forever. Wanna fuck you while I can.”

Eijirou’s large hands squeezed his hips. “You know, we can still do stuff like that after, right? I’ll… I’ll still want you then, too.”

And there was the confirmation he’d needed. Katsuki smirked. “If you don’t fuck me in the next two seconds, I’m gonna walk outta here.”

“Oh? Gonna walk home naked?” he teased.

Before Katsuki could respond, Eijirou surged forward and kissed him again, rolling them so that Katsuki was on his back on the floor. He adjusted his legs, spreading them as Eijirou’s hands lightly traced over his skin. Goosebumps prickled to life, and the redhead chuckled into the kiss.

“Gave you goosebumps.”

“Shut up and fuck me.”





He grinned as he slid his hand up the inside of Katsuki’s thigh and between his legs. Thick fingers pushed between the folds of Katsuki’s vagina, and he grunted, eyelids fluttering shut. Eijirou’s fingers pushed deeper, and Katsuki gasped when they curled and rubbed over something sensitive inside of him.

His thumb brushed over Katsuki’s clit, and as Eijirou fucked him on his fingers, he pulled his boxers down.

“You sure you want this?”

“Eijirou, I swear to fucking god.”

“Just had to make sure,” he murmured before leaning back. He kept fucking Katsuki on his fingers as he undid the stupid R belt around his hips and pushed his pants down.

Katsuki bit his lip and watched with hooded eyes as Eijirou pulled his cock out, slowly teasing it until it was hard, thick, and long.

“I’ve got a condom in my locker. Hang on.”

The blonde gave a frustrated groan when Eijirou pulled his fingers out. He returned a few seconds later, unrolling the condom over his cock, and shit. Katsuki had seen it before, of course. As Eijirou’s best friend, the two of them had seen each other naked more than once, but this--this was amazing.

He’d never seen him hard before. Not like this.

Katsuki kicked his boxers off the rest of the way, trying not to think about how anyone could walk in on them. He owned the agency, so it wasn’t like he’d get fired. It would just be very unprofessional, and--


The thick tip of Eijirou’s dick was lined up with Katsuki’s vagina. His broad frame forced Katsuki’s legs further apart.

“You ready?”

He tangled his hands in Eijirou’s red hair before nodding. “Fucking do me, asshole.”

He chuckled before kissing up Katsuki’s shoulders and neck. One hand squeezed his breast before rolling his nipple between his fingers. “Yeah?”

“Eijirou, I fucking swear, I’ll--”

A sharp, slow thrust and Eijirou’s cock sinking into him cut his words off, a moan breaking them into pieces.

“Holy fuck, you feel amazing,” he breathed out.

Katsuki grappled Eijirou’s shoulders and wrapped his legs around his hips, forcing him deeper. The stretch was incredible. Every inch of his body tingled from the epicenter of his vagina, and he gasped, head tilting back, exposing his throat.

Eijirou started slow, his thrusts almost lazy. Kisses were lavished across Katsuki’s neck and chest before their lips met again.

Soft gasps and moans filled the locker room, and Katsuki’s eyes fluttered as Eijirou, the man he’d wanted for years, fucked into him. The pace picked up, and Katsuki groaned as the other man’s balls slapped against his butt.

The tempo of their sex increased, faster and faster, and Eijirou panted out, “Not… not gonna last. Shit… feel so--ah!--so fucking good, Kat.”

“Holy crap,” he whined. Something inside him broke, his cunt becoming wetter than normal as lightning split across his vision. His body trembled as he came, and Eijirou sped up his pace, fingers sliding down and rubbing over Katsuki’s clit as he fucked into him.

“Kat… holy crap, Kat… g-gonna… oh…”

The thought of Eijirou cumming inside him, coupled with him toying with his clit, sent Katsuki hurtling over the edge again. He squeezed his legs around Eijirou, fingers raking over his skin. A wave of hardening rolled over the other man, and Eijirou moaned.

“C-cumming… oh god…”

His thrusts became shorter and more concentrated, and Katsuki’s hips lifted, grinding down as he came a third time, eyes rolling back as the locker room echoed with their pleasured moans.