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The shitty nerd wasn’t paying attention to him the one time he should have been.
Leaning over the kitchen table, ass sticking out in Deku’s direction, he was decked out in his shortest soccer shorts — shrunk in the wash, for good measure — and his favourite tank top — which not only was low cut but also tight around the chest, pushing his impressive tits up, giving a good eyeful of his cleavage. Katsuki knew he looked good .
But for some reason, that shitty nerd was sitting on the sofa with the frog girl, chattering away about the effect of the seasons on her internal biological clock. After another irritating few moments of him waving his ass around and Deku completely ignoring him, he huffed, grabbing a chair, letting it screech across the tiles, and plopped down into it.
Tsuyu heard the petty racket he made and turned to give him a faintly pitying look, but Deku’s excited rambling stole her attention in a quick moment. Katsuki scowled, pulling his shirt a bit lower and grumpily arching his back against the chair, pushing his tits out, just in case the shit head happened to look over.
That shitty nerd wasn’t ignoring him, per se. But he wasn’t paying attention. And he should have been because Katsuki was trying his damn hardest to get his attention!
Katsuki rued the days when the nerd followed him around everywhere with prompting. He’d really let those days go to waste. It was tragic, really, but it wasn’t like he could blame himself — how was he supposed to know that tiny crybaby of a green bean would turn so fucking hot?! The sudden increase in height, the mild tan, the way he was built — and hung — like a fucking tree — they were all unexpected (but not unwelcome) developments.
“Damn,” Jirou commented, leaving the kitchen with a bag of chips. “You really out here looking like a snack.” She took a look at the cause of his ire and snickered. “It’s too bad Midoriya’s not hungry.”
“Shut up, jack-head,” Katsuki growled, crossing his arms over his chest to further push his chest up. He shot her a glare when she snickered, but she just sent him a look of pity — which he ignored — and walked away.
It took way too long for the shitty nerd to finally end his conversation about fucking migratory instincts in amphibian-quirked people with Tsuyu. Why the hell did he care so much about that, anyway? But finally, Deku got up from the sofa and headed towards the kitchen, just as Katsuki knew he would. Deku always got parched after an intense rambling session.
Sitting at the edge of the table right next to the kitchen, Katsuki was unmistakable. “Oh, Kacchan!” Deku finally greeted him, that dumb little smile growing on his overly freckled face. His freckles had increased exponentially as he tanned, leaving him with soft spots all over his ridiculously large body. “Did you read over Aizawa-Sensei’s comments on our group practice fo—”
“Yeah, I fucking aced it of course,” he muttered, grumpy, using his crossed arms to further push his chest up.
Deku’s eyes didn’t stray from his face for even a moment.
“Of course, Kacchan is amazing,” Deku agreed easily. Katsuki glowered. What was amazing was his tits and ass , and Deku was not appreciating them properly.
Katsuki decided to take a different approach and stood up before Deku’s pea-sized brain got distracted by something like the fucking wallpaper again, and stretched himself out in front of Deku, very intentionally and obviously sticking his out his scantily-clad ass. Turning his head to watch Deku’s reaction, he slowly, sensually arched his back.
Deku didn’t flinch. “Oh, I should stretch too, I’ve been sitting for a while,” Deku mumbled, “We used our pectoral muscles more than average in today’s exercise, so I guess the strain on our shoulders is —”
“Fucking hell,” Sero said in pity, watching Katsuki’s attempt at getting Deku's attention completely and utterly fail as the shithead walked away, still mumbling to himself, leaving an angry, bewildered, hot blond.
Katsuki scowled, deciding to go to bed since he clearly wasn’t getting any tail. Or head. Or anything but blue balls, really.
He passed the group of extras coming from the showers. He ignored the familiar sighs and sympathetic looks, scowling even harder when Kirishima patted his shoulder as he stormed past them.
“Begone, thot,” Mineta said, eyeing Katsuki in disgust. Katsuki paused, and in one swift move, shoved him out the window. Mineta tried to use his balls to stick to the wall and clamber back in like the disgusting pest he was, but Sero shut the window on his fingers. Kaminari and Mina both gave him the finger over Sero’s shoulder while Kirishima distracted their class president.
Ignoring Mineta stuck and wailing outside, Mina slung an arm around Katsuki’s shoulders. “Again? Honestly, Bakubaku, I’m really disappointed.”
Katsuki glowered. “ You’re disappointed?”
“Listen,” she pulled him closer, horns stabbing his chin. He smacked her irritably, but she didn’t let go. “I’ve got something for you. You don’t have anything planned for tomorrow, do you?”
Katsuki frowned, eyeing her warily, but he was pretty desperate. “Why.”
Mina smirked. “Well, I have a friend that has a friend that has a friend that has a quirk that has some pretty… well, big effects.” He glared at her. She took the hint and continued. “You see, it’ll, well, increase the chances of— “
“What’s your point,” he interrupted, impatient.
Mina sighed dramatically, but reached into her pocket and pulled out something from a plastic bag. Winking, she grabbed his hand and put two small pieces in it. He stared blankly. Pills.
“They’ll get you the attention you want, where you want it,” she smirked.
Katsuki eyed the pills. Two simple, one in a peachy colour, the other cherry. Mina continued as Katsuki contemplated whether taking unspecified pills coming from a plastic bag from Mina’s pocket was a bad idea. Then again, Mina was responsible for Uraraka and that uptight, proper Iida hooking up, so she did have some credibility...
“— and they’ll last a few hours, so make sure you and Midoriya are not busy when you take the— oh.” Mina blinked as Katsuki popped them and swallowed them dry.
She stared for a moment, before smirking again. “Fair. Live your best life, Bakuhoe,” she gave him a wink, patting his shoulder.
It was a while later in his room that he noticed a difference. It wasn’t anything significant, just that the already-tight shorts he was wearing commando were starting to give him a wedgie. He shifted uncomfortably for a moment because he only liked seamless thongs, but that didn’t ease his discomfort.
He grimaced when the rough cloth brushed against his sensitive taint. Looking down to rearrange his balls, he found himself distracted quite quickly.
The tank top made his tits look big, but not that big.
Katsuki frowned, getting up to check himself out in the washroom mirror. His body weight felt distributed weirdly, making him heavier in a way he wasn’t, but wished he was, and every step had his seeming to bobble more than it usually did. It felt strangely pleasant, he thought.
He gasped when he saw himself. His tits were huge . He was already a C cup, but they— they were currently popping out of his chest, barely constrained by his tank top, with a softness he didn’t typically have. Katsuki grabbed one, and his mouth fell open. They were so damn sensitive! A singular touch didn’t have him nutting, but when he grabbed them with both hands and began fondling them, he felt like he might. Every pleasant tingle and sensation he usually felt was amplified. His large tits made his waist look even thinner, and his nipples were extra sensitive, visible through his shirt.
Turning to the side to see himself from a different angle, he realized with no small amount of delighted surprise that his ass was fat . His ass was always his least favourite part of himself, being unfortunately flat, but he couldn’t quite control his weight distribution, and plus, bulking up below would hinder the quasi-flight he did with his quirk. That left to a pretty unfortunate circumstance where his ass wasn’t as thicc as he’d like.
But at the moment? He leaned forward on his toes before dropping back to the floor, and the rippling sensation of his ass cheeks smacking made him bite back a moan.
He wasn’t just thicc. He was dummy thicc.
Belatedly, he realized that this must be the effect of Mina’s shady pills. He couldn’t help a grin. Sometimes those guys weren’t that bad to have around.
While he wanted to stare at and appreciate his enhanced body a bit longer, he knew he had to make the most of this opportunity — he could use this to get a certain dumbass to, at long last, appreciate his body. Mind set, he returned to his bedroom
The bounce of his tits and clap of his ass cheeks as he walked had him stiff in his already tight shorts. Fuck, with how fat his ass was, they were straight up booty shorts.
Katsuki cursed, realizing the best of his lingerie was in the laundry. Fuck, he needed something! After a moment of consideration, he sat down on the bed, biting his lip at the feeling of his fat, bouncy ass beneath him, and grabbed his phone.
I need a decent bra , he sent to Yaoyorozu.
It only took a moment to get a response. Lace or no lace?
Lace for sure , he texted back. And make it for boobs your size .
Bakugo, we have the same chest size .
Katsuki scowled. Fine. Two sizes bigger.
He had a brilliant idea a moment later. And get Deku to bring it to me .
It took a minute for the next message to arrive. He says he’ll bring them down in a minute. Have fun, stay safe, and good luck!
He sent back a thumbs-up, making a note to buy her the sweets she liked next time he went to the mall, and tossed his phone to the side, smirking as he looked down at his body.
Katsuki knew his body was always hot, but his tits were just so damn pretty . He pulled his left tit out of his tank, assessing it. He could feel the increased weight pulling on his shoulders and back, the way his centre of weight had shifted. Katsuki cupped his boob, feeling his dick twitch as he stared down at himself. It was big — even Deku’s unnecessarily big hands wouldn’t be able to grab it. It wasn’t saggy, more like a larger, if softer version of the impressive pecs he already had. Rubbing a finger over his nipple, Katsuki watched it stiffen, feeling a certain familiar heat pooling in his gut.
A knock on the door jolted him out of his self-appreciation. “Kacchan?” Finally, he thought smugly. “I brought the thing from Yaoyorozu?”
Katsuki shot up, tits and ass bouncing and smacking, but paused. Hastily shoving his boob back into his shirt, he turned the desk lamp on and dimmed the main lights. His ass jiggled with every step, only heightening his sense of anticipation and arousal, and he tossed himself on his bed arranging himself to be painted like one of those french girls.
“Get in here, nerd,” he called out, a hint of excitement in his voice.
“Uh, alright,” Deku opened the door, holding out a simple bio-degradable bag, his large, thick body silhouetted by the light from the hallway. “Kacchan? Why are the lights off?”
Katsuki smirked, savouring the confusion on Deku’s face. From that angle, he wouldn’t be able to see. “Close the door behind you, Deku.” Deku blinked but did just that. “Lock it.”
Deku turned back, giving him a confused look, but still followed his instructions. “O...Okay?”
When that was done, he walked over the bed, hand still tentatively holding the bag out. “Um, is everything okay?” Katsuki finally turned over, stretching his body out, sticking his ass out in Deku’s direction and wiggling it, twisting his body so his boobs were fully visible, almost bulging out of his tank.
Even an idiot as oblivious as Deku couldn’t ignore the swell of his massive tits and ass, the flesh popping out of his tight clothing. He watched, smug, as Deku’s mouth fell open, as his dumb-baby ass eyes widened, and snickered at how the nerd’s body stilled when he took a visibly choked breath.
“Oh,” Deku gulped, cheeks heating. “Um.” His eyes trailed over Katsuki’s body, a visible shudder running through his body as he saw the booty shorts on Katsuki’s fat ass. “Uh.” Deku shifted uncomfortably, and Katsuki was very pleased to see a certain lump forming in the nerd’s ridiculous bright yellow All-Might sweats.
“Give me that,” his voice was low, sultry, as he gestured to the bag. It took a long moment before Deku was able to pry his eyes away from Katsuki’s filled-out body, but he did eventually remember he was holding something.
“Oh. Y-yeah. Uh. Here.” he held out the bag stiffly, robotically.
No,” Katsuki clicked his tongue. “Take it out, and give it to me, shit head.”
Deku’s mouth widened and he looked shell-shocked, excited for a quick moment before he shook his head and cleared his throat. “Right, you mean. Take out, what’s in the bag. Give you the uh. Contents.”
Katsuki smirked. “Yeah. Give it to me. ”
“Give it to you,” Deku repeated dumbly. “Yeah. I’ll. Uh. Do that.”
“Hurry up, nerd,” he purred, turning over just enough to cause his fat ass to wiggle. Deku fumbled, nearly dropping the bag, but did manage to get his hand in it.
He could see the moment when Deku touched the contents because the confusion was clear on his face. Katsuki snickered at Deku’s slow realization as he slowly pulled the fabric out.
The disbelief on Deku’s face as he held up the lacy bra was almost enough to make up for his earlier transgressions of ignoring him.
“Well?” Katsuki asked, sultry. “Come on, give it to me.”
Deku’s attention momentarily shifted to the bag again, and when he turned it upside down, Katsuki was pleasantly surprised to see that Yaoyorozu had added an extra goody. A matching lacy seamless thong.
“Ah.” Deku stared at the thong and bra in his hand, looking like he wasn’t sure whether his soul or a certain something else was about to eject out of his body. He was visibly hard, but even more so confused. Katsuki snickered. It was likely the first time he was touching any sexy underwear that wasn’t his mother’s. “Kacchan, w-what is this...?” his gaze darted stared between the underwear and Katsuki like he wasn’t sure if Katsuki was trying to trick him or not.
“Obviously it’s for me, shithead,” he growled playfully, tossing one leg over the other. Deku’s eyes shot back to his plush rear end. “Even an idiot like you can guess what I’m gonna do with some clothing, right?”
Deku’s mouth opened and closed a few times, his cheeks turning an even darker red as he very clearly began entertaining the idea of Katsuki in the skimpy garments he was holding. His head bobbled in that way that indicated he wasn’t sure if he wanted to shake his head no or nod yes.
“I want it on me.” Katsuki uncrossed his legs, leaning back to showing off his long, firm legs and the voluptuous curve of his amplified tits. His enlarged, bouncy breasts were just barely covered by his top, and he could see how Deku’s eyes were drawn to where the pebbled nipples were evident through the fabric.
“How about you help me?” Katsuki shot him a predatory smirk.
Deku looked half gone, but when Katsuki’s words clicked he gaped. “Help?”
“Yeah,” Katsuki gestured to the bra Deku was still holding. Deku stared at it, bewildered. “It’s not easy to put that on, you know, I might need some help.”
Obviously, Katsuki was lying, He wasn’t fucking incompetent. He could put on a bra with no problem, but of course, he would take any and all excuses to have Deku’s hands all over him.
Deku looked like he was on the verge of passing out. “Help. Kacchan.” Not a phrase he got to use often if Katsuki had anything to say about the matter. Deku looked excited, and so did the growing lump in his pants. “I-I’ll help Kacchan with anything! W-whatever he needs!”
“Hmph.” He coyly turned over so he was facing the wall instead of Deku and pulled off his tank top, causing his breasts to bounce as they were set free.
He could hear Deku’s sharp inhale, and couldn’t help a huff of amusement. It wasn’t as if his back was anything that would get Deku nutting — well, he did have a nice back — but he knew Deku would find him irresistible with the way he was arched, his fat ass right facing the nerd, practically falling out of his tight shorts, with how his tits were just barely hidden, the shadow of them visible on the wall, the low light casting a faint glow to his skin. He knew he made a pretty sight.
“Are you gonna sit there all day, Deku,” he reached out behind him expectantly.
Deku stiffly handed over the bra. Katsuki shoved his arms through the holes, leaving it open at the back.
“Clasp it up,” he ordered. Deku tentatively sat on the bed, hands hovering over Katsuki’s back. “Hurry up, nerd!” he snapped when the nerd’s silence veered into ‘about to start another inane mumbling session’ territory.
“Ah, s-sorry Kacchan,” he stuttered, tentatively putting a hand on Katsuki’s back as he grabbed a clasp.
Deku’s hand slid down his shoulder, large warm hands skimming his body from shoulder to waist. Katsuki couldn’t help the shiver that ran through his body as Deku’s hands roamed his back. He leaned back, sitting on his haunches, pressing himself against Deku. Deku inhaled sharply, hands grabbing Katsuki’s waist in surprise at the sudden movement, leaving the blond startled for a moment when he looked down and saw how Deku’s could wrap his hands around almost the entirety of his waist.
His mouth parted, looking down at those scarred hands. Fuck, they were so big. Katsuki could cup his tits with some excess, but Deku’s hands would probably be able to grab them in their entirety. Fuck, those fingers. Katsuki had had many a dream about those large, slightly crooked fingers. He wondered how far inside him they would reach.
The nerd’s current position resulted in his every breath ghosting the back of Katsuki’s neck, causing goosebumps to rise all over his body. The contrast of the cool air of the room against the warm puffs tickling the back of his neck and the warm hands wrapped around his waist had him hypersensitive. He could feel his palms beginning to sweat from how fast his heart was beating and subtly wiped them on the bed sheets before pressing back a bit closer.
“Well?” he teased after a moment of acclimatization to Deku’s presence, his heat, his smell, all pressed so close to his behind. “Are you gonna put it on or what?”
“I.” Deku audibly gulped, slowly dragging his hands up from Katsuki’s waist to his sides where the clasps were hanging. “Y-yeah. Yeah. Yes.”
Katsuki never expected that the act of having a bra put on him would be so erotic, but maybe it was just because it was Deku putting it on him that he was so aroused. His voluptuous breasts were already extra sensitive, nipples hard from exposure to the cool air, and having the bra pulled against them made him swallow hard. Looking down and seeing his pretty tits covered in the lacy, sexy material, having Deku clasp it up, Deku using that as an excuse to touch him and feel him up, knowing that Deku was hard behind him, Katsuki felt the pooling heat in his gut spread through his entire body, heating him up, making him hungry for more .
It took Deku a moment to figure out how the bra worked, but he wasn’t a nerd for nothing, and eventually had it clasped comfortably. His hands lingered on Katsuki’s back, and before the nerd wimped out, Kastuki continued. “Hurry up.”
He sensed Deku’s confusion and reached back to grab the thong from the bed before Deku could speak. “Put this on me.”
Deku gasped, jolting a bit, and suddenly, Katsuki could feel Deku’s entire erection pressed against his behind.
Katsuki ensured his head was turned away so the shitty nerd couldn’t see his victorious smile as he rubbed his ass against his erection, grinding shamelessly as he tried to make out the shape of it behind him, using his big behind. He knew very well what it looked like — they did share a locker room, after all, but feeling it pressed up against him like that was something else. This was the prick he had been craving for ages . Getting up slightly on his knees, he tried to pull down his booty shorts but was disappointed to find they wouldn’t come off. His ass was too fat.
“Deku,” he growled, annoyed. “Be useful for once.”
“I…” Deku was at a loss for words, seeing the top half of Katsuki’s fat, fleshy, expanded ass unclothed, pressed against his crotch. “I?”
“Get this off,” Katsuki snapped. “Or should I call someone else in to help out? That pretentious class president, perhaps?” he snickered.
A moment later, he gasped, feeling the cool air of the bedroom hit his body. Turning around, he realized what had happened. Deku ripped the shorts right off of him.
“No.” Deku finally answered Katsuki’s question. Katsuki saw something fiery in his eyes, something he only rarely got to see on the battlefield, or when he stirred Deku up during their training sessions. The green eyes were alight, similar to when he used his quirk, but this was a source of energy that came from within him himself. “ I will help Kacchan.”
“Oh?” Katsuki rubbed himself back against Deku teasingly, pleased at the reaction his empty threat had caused. “Well, you’re not doing a really good job of it, shitty nerd.”
Deku grabbed his hips, pulling them close together, causing Katsuki to gasp. “What does Kacchan want me to do?” he murmured. “What does Kacchan want?”
“Put the thong on me,” Katsuki ordered.
He could hear Deku’s sharp, excited inhale at his demand, could feel an excited something poking his bottom as well. He bit back a smug grin. Finally, he was going to get what he wanted.
Katsuki turned to look at Deku over his shoulder. On his hands and knees before the hunk of a nerd, his ass was right up in Deku’s face, the bra still around his tits. Deku gulped, eyes fixed on his ass. Of course, Katsuki couldn’t resist the opportunity to keep that attention there and began bouncing his ass. He was glad Mina had taught him how to twerk, because, especially, with an ass as big as his, it was sexy as fuck .
The way Deku’s eyes widened and his mouth fell open as he watched the ripples on the bouncing, jiggly ass indicated he felt the same way.
“Come on, nerd,” he purred. Are you gonna help me out here or what?” He arched his back up teasingly, shaking it at Deku.
Deku was entranced by the way it jiggled. It was so much fatter than he was used to. Katsuki noticed the way his entire body moved was different, and he couldn’t help but love it. Fully hard, his cock wept beneath him, and he was tempted to reach down and give it a yank or two, but Deku’s eyes on him felt so good, he wanted to watch Deku watch him bouncing his large ass even more.
“It’s so big,” Deku murmured, absolutely breathless. His hand reached out, but he quickly retracted it. Katsuki clicked his tongue in annoyance.
“Don’t be afraid to touch,” he demanded, annoyed. “How else are you gonna help me?”
Deku gulped, but nodded, hesitating a moment before grabbing two large handfuls of ass.
Katsuki bit his lip to muffle his moan. Deku’s large, warm hands all over his ass, cooled from the exposure to the air, made for a delightful sensation. Deku squeezed and Katsuki couldn’t hold back a whimper.
Deku’s head whipped up, his hands disappointingly flying off Katsuki’s ass. “D-does that hurt?!” he asked, panicked.
“More,” Katsuki demanded. “Do it,” he snapped a moment later when Deku just stared at his ass hesitantly. “Are you gonna be helpful or should I ask somebody else after all?” he sniped.
Deku’s eyes darkened, and he gripped Katsuki’s ass again. This time, he was very clearly using his quirk.
Katsuki couldn’t help the cry that escaped his lips. Fuck, that felt good . He knew Deku had to be using at least 10% there, gripping his ass tightly and firmly, using the quirk he had made his own to mark Katsuki his own.
“Kacchan’s butt is so big,” Deku mumbled. “If I had to say, the circumference of each individual ass cheek has increased by a fair few inches. I guess the factor of curvature has increased exponentially, so it’s at least — “
“Deku,” Katsuki moaned, loving the way the nerd was squeezing, grabbing, playing with his ass, but not really loving the nerd’s dirty talk. He’d take pity on the dumb virgin, for the sake of their cocks. “You can take measurements later, dweeb. Tell me what it looks like.”
“What it looks like?” Deku turned to the ass. “It’s… big.” Before Katsuki could bite him for that dumbass observation, he continued. “It’s bouncy, and the light reflects off it so well. It looks big and soft, yet perky. It doesn’t sag at all, even when I let go,” he let go and smacked a cheek, and Katsuki came a little. Not a lot, just a small spurt, but he couldn’t really help it, especially when he wasn’t expecting something so good. The way his ass jiggled and rippled when Deku hit it, not even using his quirk, reverberated up his spine, deep into his gut, deep into his brain, leaving him unable to think past ‘Yes, more, please ’ .
“I’ve never seen anything so round and yet perky,” Deku continued. “It’s so ripe, if I bit it, I think it would be the juiciest thing I’d ever eat,” he murmured. “It’s so soft. I wonder if the skin bruises easily,” his gaze was intense as he stared closely at the large ass, his grip tightening just a smidge.
“Deku.” Katsuki didn’t mean for it to come out as a whine. “Come on .”
“O-oh, right,” Deku blinked, shaken out of his nerd mumbling. “W-what did Kacchan want me to do again?”
Katsuki grumbled in annoyance. “Put the thong on me.”
Deku picked the thong up and stretched it out in his hands consideringly. “Hmm. It’s gonna be a tight fit.” His brow creased in the manner that indicated he was heading into a rambling spiral.
Katsuki grit his teeth and interrupted before it could start. “Come on, nerd,” he growled.
“Ah, Kacchan should turn over then,” Deku suggested. “It might be easier to get it on you that way,” he offered helpfully.
Katsuki grit his teeth but turned over, laying on his back, legs open so the nerd was sitting between them, fully exposing his flushed, leaking cock, and allowing Deku to get a good look at the bra he was wearing in its entirety.
Deku’s mouth hung open as he stared at Katsuki’s tits. Katsuki couldn’t help the rush of pride. He knew he looked hot in the bra. Lace always looked good on him. But when Deku’s eyes drifted down to his leaking cock, he could see the embarrassment and interest on his face.
“Well?” he prompted, shoving down the hint of anxiety as Deku just stared. His gaze was intense, Katsuki felt so fully exposed under his silent scrutiny. He fought the urge to press his knees together and forced his legs to wrap loosely around Deku’s waist. Deku watched the movement, eyes still aflame, lips parted, as Katsuki stretched himself out, licking his lips, giving Deku bedroom eyes, leaning back, canting his hips teasingly, spreading himself out before Deku pointedly. Even Deku wasn’t oblivious enough to not realize exactly what Katsuki’s body language was suggesting.
“K-Kacchan,” Deku stuttered, face heating. “Th-Well, y—I—this wh—” he stuttered incoherently. “Are you —?”
“What does it look like, shithead,” he snapped. What kind of nerd was he that he couldn't read between the lines? Hell, he just had to read the fucking lines.
“I— well,” Deku flushed, ducking his head down, but tentatively resting a hand on Katsuki’s thigh “I — are— are you sure?”
Katsuki stared.
“What?” he growled, frustrated, hips bucking slightly as he leaned back to glower at the nerd. He was literally naked in bed, save the fucking lacy bra, with massive tits and a fat fucking ass, cock hard, leaking, quite literally demanding that the nerd touch him, and the shithead still was asking ‘are you sure? ’
“Deku,” he started, voice threatening. “If you don’t come here right now and fuck me so hard I can’t walk straight for the next week , I will DECK YOU . Understand that, Deku ?”
“I—er,” Deku grinned nervously, excitedly. “O-okay, Kacchan!”
It was just as annoying as it was amusing to watch Deku fumble about trying to finger him, babbling about types of lubes, trying to follow a step-by-step Wikihow guide for how he expected things to go down. Katsuki was already loose, just in general, but also because he had an unsatisfying session with his favourite dildo earlier that day, so thankfully that sped things up when Deku realized his fingers sunk in quite easily.
“So loose, ” Deku mumbled as he easily shoved four fingers in and out, curling them curiously, causing Katsuki to jolt and let out a sharp gasp as his prostate was ceaselessly stimulated. “I didn’t know Kacchan’s asshole would be so soft and loose. Kacchan is so slutty. I wonder what everybody would think of Kacchan like this, loose, begging on my fingers. He looks so pretty.“
Deku was unrelenting, fingering him with purpose as he mumbled to himself. Katsuki felt heady. Each little twitch of Deku’s fingers had his cock weeping, his whole body jolting, not because fingers in his ass or having his prostate stimulated was something new to him, but because it was finally Deku in his ass. His legs spread wider around Deku, inviting the oak tree of a man in, closer.
For once, he didn’t have to prompt Deku into doing something. Deku stripped himself — thank god, Katsuki thought, getting an eyeful of those washboard abs, those thick thighs, the arms that rivaled his own — and grabbed his cock with a relieved moan, giving it a few pumps as he brought it closer, pressing it tentatively but eagerly against Katsuki’s twitching hole. Katsuki glared at him when Deku mentioned a condom - he wanted it all and it wasn’t like either of them had had sex before. He was taking Deku’s first everything .
Grabbing Deku’s cock, earning a choked moan from the man, Katsuki rubbed it up and down, coating the entire massive thing in lube. Deku’s face was pinched, and it made Katsuki want to tease him — hell, the nerd deserved it after teasing him for so long — and it was a very tempting thought, having Deku deep down his throat, but what he wanted most was Deku deep in another part of him, so he promised himself he would fulfill those desires in the near future, and pressed the tip to his hole purposefully, wrapping his legs tighter around Deku’s hips, urging him forward, in .
He felt near euphoric when Deku finally fucked into him. Katsuki could barely keep himself still as Deku thrust slowly, watching Katsuki’s reactions carefully, doing his best to be as considerate and gentle as possible.
And while he appreciated that, he didn’t want that. He wanted to be fucked .
“Deku,” he demanded, hating the whiny pitch of his voice. “F— just — ah!” Katsuki broke off into a loud gasp as Deku thrust a bit deeper into him. “Fu— fuck me, shithead, or els—”
Katsuki’s words dissolved into whimpers when Deku did just that .
Everything was so hot. Deku picked up his pace, quickly coming to realize just how much Katsuki loved it when he grabbed Katsuki by the waist, hips, thighs, dug his fingers in, rammed in full throttle. He wasn’t a nerd for nothing, after all.
He really was a nerd, Katsuki thought when he realized Deku was experimenting and mentally documenting Katsuki’s reaction to different things. Deku tried thrusting certain ways — deep and slow, fast and hard, various combinations in between, at different angles.
His hands wandered, skimming over every part of Katsuki he could reach. He touched everything he could, digging his fingers into Katsuki’s legs, caressing his inner thigh, rubbing his hip bone, gripping his waist, grabbing his tits — Deku loved the bra, Katsuki was pleased to find, and kept it on while fondled his large, sensitive breasts with the hunger of a starving man.
The intensity with which he stared at Katsuki made him burn —or feel like he was going to burn something. He was glad he had the fireproof bed sheets out today. After wanting it for so long, having Deku so close to him was almost too much, watching Deku live out his long-standing fantasies made him feel as horny and hot as it did overwhelmed and heady, pushing him into a space where nothing in the world mattered — or even existed — but him and Deku. That familiar green hair, still fluffy from an earlier shower, hung over his face as he leaned down over Katsuki until their faces were inches apart. Through teary eyes, he stared at the dumb nerd. Deku was flushed as he lingered above Katsuki, hesitating, but Katsuki reached out and pulled him closer, connecting their lips in, frankly, probably the least sexy kiss ever.
There was no fight — why would Katsuki fight against something he’d wanted for so long?—, there was bottomless desire and the raw sensuality of two inexperienced but incredibly passionate people locked in a world of their own. Deku was just as eager as he was, Katsuki was pleased to find, and so he openly encouraged the nerd’s curious movements.
He ran his fingers through that ridiculous messy green hair, pulling the idiot in closer, parting his lips to allow Deku full access, tongues slipping against each other's as they relished the first of hopefully many makeouts, chasing each other’s lips whenever the other tried to pull back, not letting each other go until they were both breathless, and even then regretting it, missing the other’s lips as soon as they parted.
When Deku pulled leaned back to pull out of Katsuki’s ass, Katsuki was immediately incensed, but Deku ignored his protests, turning his body over.
Katsuki’s growls went unheard as the nerd mumbled to himself quietly. Deku pressed his hand into Katsuki’s back to push him down on his hands and knees, arranging the blond until he was satisfied.
Katsuki continued protesting to rile up the nerd, but he had absolutely no problem with his current position, face pressed into the mattress, ass up, back arched as Deku pressed him down hard, pressed into him hard. His moans very quickly belied his protests, and Katsuki soon gave up the pretense, smacking his ass back into Deku in harmony with the thrusts.
A part of Katsuki regretted how neither he nor Deku could see his pretty tits bouncing in the bra anymore, but the way this position allowed Deku to play with his fat ass more than made up for it. Deku left one hand gripping his ass, the other one holding tight onto Katsuki’s waist as his whole body was jarred with every thrust. Their moans rang out in the confines of his room like a dulcet, harmonious symphony he wanted to hear every day for the rest of his life.
Katsuki was delighted to be helpless underneath the nerd as Deku pounded him down into the mattress until, suddenly, Deku slowed his movements. He waited a moment, expecting the nerd to be experimenting again, cracking one eye open to peer up at him, curious about what Deku was thinking of but also annoyed at him for stopping.
“Uh...” Deku bit his lip, movements sluggish as he stared contemplatively at Katsuki. Katsuki groaned in annoyance.
“Your cock is literally in my ass right now,” he snapped. “If you have something to say, just say it for fuck’s sake!” He might actually get soft if Deku started mumbling again.
“Ah, well,” Deku squeaked out, before clearing his throat. “Kacchan,” Deku’s eyes flickered to Katsuki’s expanded ass, something vaguely playful entering his eyes as he took in the large mounds, the plump peaches, red and ripe from the smack of skin against skin. “You know what to do with that big fat butt,” Deku couldn’t help the mirth in his voice as he halted his thrusting for a moment to lean down and whisper in Katsuki’s ear.
“Wiggle, wiggle, wiggle.”
“You piece of ahh-! ” Katsuki moaned as he was suddenly pounded into.
“Come on, wiggle like you're tryna make your ass fall off,” he rapped, thrusting deep, balls smacking against Katsuki’s. “Hella thick I wanna smash it all,” he spanked Katsuki’s ass.
“Now speed up,” Katsuki bit back, sending a challenging smirk over his shoulder, unable to help the tinge of amusement, meeting the challenge head on, wiggling his ass at Deku. “Booty me down. Booty me down. ”
Deku’s eyes darkened. “Left ass cheek,” he smacked the left cheek. “Right cheek now.” Another hard smack.
Katsuki bit his lip to muffle his gasps of delight. Making eye contact with Deku, he gave the most exaggerated seductive look he could, arching his back. “Wanna hit it from the back? Let me arch my back, once I arch my back that means attack this bussy,” he could see Deku’s brow furrow in confusion, so he smirked, switching to the chorus.
“Hump me, fuck me, daddy betta make me choke,” he moaned, fake and obnoxiously, smacking his ass back against Deku, hard . “You better~ Hump me, fuck me, my tunnel loves the deep— ah!”
Deku lost first, Katsuki was proud to say. He grabbed Katsuki’s arms and crossed them behind his back, pinning there with one hand and using the other to shove Katsuki face-first into the mattress. There were no sexual lyrics after that. Just Katsuki getting the dicking of his dreams.
Deku’s large, scarred hands grabbed his fat ass cheeks, the juicy mounds of flesh rippling with every thrust as he smacked against them ceaselessly, each slap of skin echoing in the room, accompanied by the obscene squelches of their fucking. Everything about it made Katsuki harder, arch his back higher, bounce his ass harder, pressing his massive breasts against the mattress harder.
Fucked breathless, Katsuki was drooling into the pillow, thoughtless, unable to do anything but feel and love the way he was stuffed so thoroughly, repeatedly. It was therapeutic, he thought, getting a good dicking. Or maybe it was just being with Deku.
Said nerd smacked his ass again, hard, pulling a gasp out of Katsuki. He couldn’t help loving the way his fat cheeks bounced and slap with every thrust, but when Deku smacked him on top of that? Katsuki’s hips bucked. Obscene, wanton noises escaped him.
Deku repeated the action, following the spank with gentle caresses on the burning area, the touches contrasting so erotically. He knew his ass was a dark red — he sincerely hoped that it would be bruised even after the quirk wore off.
The shitty nerd continued playing with Katsuki — alternating between smacking his ass with his quirk, smacking him without out it, and gentle, tender, almost loving touches. He rubbed the skin tenderly, almost affectionately, before bringing his hand down with enough force that Katsuki’s entire body jolted, his cries of pleasure likely ringing throughout the dorm. It drove Katsuki wild, being so unsure what each next move was, heightening his pleasure as his ass was thrust into ceaselessly.
It wasn’t long before Katsuki found himself brought up to the edge. Deku smacked his ass three times in succession — he was so close— so close, if Deku did that again—he was so close —!
Deku immediately slowed his movements.
Katsuki couldn’t help the loud, frustrated whine that escaped his lips. He arched his back further, pressed his hips back desperately, trying to grind himself back on that cock, fuck himself back on it, get it in him, fucking him—!
His movements became increasingly desperate and frustrated. Katsuki gripped the sheets, feeling his palms heat up and barely able to contain his explosions as his frustration and desperation grew.
“Deku,” he demanded, angry. His eyes were blurred with tears, but he turned back to glare at the nerd. Deku was already watching him, his eyes alight, intense, aroused. Katsuki glowered through his teary eyes, trying to press his hips back on Deku’s cock, but Deku grabbed his fat ass cheeks, firmly squeezing the large, fleshy mounds.
Katsuki could see the moment he activated his quirk was activated — he could feel it in how Deku’s fingers dug in, grabbing his ass, his hips — that would leave marks, Katsuki would be very smug about that later, when he was less desperate to just cum — but he also saw it before him, saw Deku’s hungry eyes turn downright predatory, grabbing Katsuki’s hips and moving them slowly on his cock, with purpose — to drive Katsuki mad.
And drive him mad it did. Katsuki tried to buck his hips, tried to wiggle or grind or bounce backwards, but he was no match to Deku using so much of his quirk, One For All rippling through his arms to keep Katsuki firm, unable to move on his cock, controlling Katsuki’s body, tortuously slow, leisurely, fucking into Katsuki like he was nothing but the shitty nerd’s fuckhole, burning Katsuki to the core until he was helpless to just whine and plead for him to move.
“Please,” Katsuki was so frustrated, he had never been harder, so desperate to cum. He wanted to grind back against Deku or bounce back on his cock or ride him or — shit, he wanted something , he wanted Deku’s cock , he wanted to be fucked , but Deku was just watching him, he wasn’t letting him, he needed— Deku was— “Dekuu,” he sobbed, voice whiny and broken, “Pleaase!”
“Good,” Deku said, absolutely breathless, entranced with the sobbing blond on his cock. “Good, fuck, Kacchan, you’re so fucking good , so slutty , so pretty, such a beautiful whore for me, so desperate, so beautiful ,” he muttered mindlessly as he finally resumed his thrusting, still too slow, making Katsuki whine eagerly, impatiently. The filth Deku was spouting made him shiver with excitement, this was the idiot nerd Deku saying such nasty things, all for him, only for him — he wanted to hear Deku tell him more — how good and pretty and slutty he was—
Every thrust was so deep and hard inside him, hitting his most sensitive parts, causing his cock to leak furiously, leaving him wanting nothing but more, more, more , and he breathlessly demanded just that.
Deku didn’t hesitate, pounding him until he was sobbing shamelessly, whining and whimpering loudly. He could barely hear the obscene wet noises, the smacks of skin against skin, but he could definitely feel it. His fat ass jiggled with every unrelenting, forceful, deep thrust, his tits bouncing even while constrained by his bra, Deku’s tight grip around his waist leaving him helpless to the nerd’s whims — it all brought him right back up to where he was before — on the edge of busting, needing just a tiny bit more until he fully came undone.
“—Kacchan is so thicc, his ass is so fat , Kacchan’s tits are so pretty and slutty — look at that skimpy bra — Kacchan begs for cock so sweetly — so good, such a good slut for me,” Deku babbled, voice strained but unfaltering as he thrust continuously.
Katsuki couldn’t hold back — the words were his undoing, bringing him clear over the edge. “Y— yes , fuck, Deku ,” he wailed as cum spurted from his aching cock, realizing proudly that this was the first time he managed to cum completely untouched.
Overstimulated, he couldn’t help the whimpers that escaped him as Deku continued to fuck into him with bruising force, pounding faster and harder as he reached his own orgasm. Every thrust had his extra-sensitive hole twitching and fluttering, his body unable to handle the sensations but his mind loving them. It didn’t take long until Deku was moaning hot and heavy, grinding deep inside, leaving Katsuki gasping and near-sobbing as he felt Deku coming inside him, filling him, his overstimulated ass clenching as he savoured the feeling of being stuffed full and deep, savouring the feeling of Deku collapsing on top of him, his large, heavy body pinning Katsuki to the mattress.
Well-fucked, sweaty and sated, Katsuki would have been content to lie there in that position, would have loved to fall asleep stretched full on Deku’s cock, with Deku’s weight pressing him down and keeping him there. But the nerd couldn’t ever make things easy for him. After the fourth nervous cough, he whipped his around to glare at the nerd, their faces only inches away from each other.
“K...Kacchan,” Deku looked incredibly embarrassed, and from this close, Katsuki could see the sheen of drying sweat, the plump lips he kept biting, the freckled cheeks covered in an unfairly attractive pink.
Deku shifted, trying to move his head back, before rethinking that, seeing as how he was still seated deep in Katsuki’s ass, with Katsuki clearly having no plans for them to move from said position and flushed deeper, refusing to make eye contact. Katsuki was filled with an equal amount of amusement and smugness. Of course, Deku would be embarrassed after they fucked so loud the entire dorm heard.
“I— er, I should have asked this earlier.”
The smirk dropped from his face. Katsuki ground his teeth, feeling his heart beat faster and harder until he could hear it echoing in his ears as he considered the nerd’s words. He swallowed, dry throat clicking, fisting the sheets below him. He forced himself to bite the bullet - Deku was in his ass, it wasn’t a secret. “Yeah. So what if I do.”
Deku stared at him blankly. “What?” he asked. “Er, I was gonna ask if, you know, if you’re okay,” he gestured towards Katsuki’s impressive mounds. Both sets of them. “Like, you look, uh, really nice, — you always do! — but, um, I don’t think this is normal — wait should I take you to recovery girl?? Kacchan are you okay??”
Katsuki blinked. He couldn’t help the amused huff that escaped him a moment later.
“I’m fine,” Katsuki smirked, rolling his hips, clenching his ass tight, enjoying how the nerd gasped and twitched inside him. Deku’s cock was already in him, he might as well make good use of it. “In fact, this quirk is gonna last a few more hours. Are you gonna be able to get it up again... or should I go find Icyhot?”
Seeing Deku’s eyes light up with an intensity that would burn a lesser being, feeling a large hand tighten around Katsuki’s waist in an unmistakably possessive gesture, Katsuki couldn’t hide his victorious, predatory grin.
“Nope,” Katsuki tossed the arm off him easily. In one swift move, he shoved Deku down on the mattress and sneered at him smugly from above, still seated firmly on his cock.
“This time, it’s my turn. ”