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"Dude, I'm hung!"
It's a terrible discussion to be having, really. Katsuki's such a prude- he couldn't even make it through sex ed without squirming uncomfortably. He isn't like his friends, with their circle jerks and pissing contests.
(Well, he's pretty sure they don't actually do all that, but they definitely act like it.)
And yet here he is, three years after he barely survived listening to Shouta Aizawa monotonously drone on about the anatomy of genitalia, apparently about to get into a dick-measuring contest with Eijirou Kirishima.
"You're not 'hung,' dumbass. I've been on T for longer than you, and I know what my dick looks like." He sneers. "It's not exactly something to brag about."
"No, you don't understand." Eijirou giggles. "This is, like, a recent development. It's like the T is hitting me harder than usual. My cock is huge, you just gotta believe me!"
"I swear to god, Eijirou, if you're trying to show me your packer again-"
"No, I'm serious." He gets a look of stupid determination on his face and stands, hooking his thumbs in the waistband of his basketball shorts. "I'll prove it."
"Dude." Katsuki wrinkles his nose. "I don't really want to look at your junk."
"Not even for scientific purposes? For the sake of an argument?"
"... You're such an idiot," he mutters, rolling his eyes. "Fine. Let's see this goddamn horse cock you're allegedly- Holy shit."
So.
He wasn't... wrong.
It's not like Eijirou's packing a foot long down there or anything. He definitely still has a t-dick, just like Katsuki. But it's... different.
Bigger.
His folds look like they're fully stretched out, but he's not hard. That's just how it is now- and by the way, what the hell? Did he get put on a higher dosage?
It's not like he looks, okay? But he's seen, everyone's seen, and it did not look like that the last time Katsuki saw.
He's looking now, though. Gaping, even.
"I know, right?" Eijirou grins smugly, placing his hands on his hips. "It's like I've got a boner all the time."
"Does it... When you are..?" Katsuki stammers, still making eye contact with the thing between Eijirou's legs.
"Nah, it doesn't really get much bigger anymore. Just, like... stiffer? Kinda?" He shrugs. "Pretty sweet, huh?"
"Ye- What? No, put it away!" Katsuki snaps, covering his eyes. "You're such a weirdo!"
"C'mon, we see each other naked all the time. It's no biggie."
He pulls his pants up anyways, and Katsuki briefly mourns the loss of his view.
It was so... fat. Eijirou has a fat cock, and now that's something that he just has to live with and be normal about.
Is this how cis dudes feel when they find out their friends have bigger dicks than them? He always imagined it would be more like jealousy, not this odd fascination that he's experiencing. It's so weird being a guy.
"Hey." Eijirou sits criss-cross in front of him, and his hair flops in that cute way that makes Katsuki want to run his fingers through it. "You good?"
"Hah?" He furrows his brow. "I'm fine."
"Okay, just checkin'. You got a little quiet, is all." He leans back, knees bent and shoulders pressed to the floor.
Katsuki could just...
If he squints...
"What the fuck..." He breathes.
He can see Eijirou's dick print.
"What's up?" Eijirou asks, his legs falling open. Katsuki groans and smacks his forehead.
"The dick thing got to me."
That makes him sit back up.
"Did I do something wrong?" He asks, worried. "I wasn't trying to perv on you or make you dysphoric or anything-"
"No, fuck you, you're fine." He grabs a pillow and sits up, hugging it to his chest. "I've just never seen one that big before."
"I get that a lot."
"Shut up!" Katsuki chucks the pillow at his stupid laughing face and huffs. "You know what I mean! Like- Like a trans dick! I haven't seen one that looks like yours, even in diagrams and shit."
"I don't think it's that weird. I've definitely seen ones like mine in porn before." He blinks, suddenly shocked. "Wait, do you not watch trans porn?!"
Katsuki doesn't watch any porn. He prefers to read smutty superhero fanfiction.
"So what?!" He grits his teeth. "Is- Are- Fuck!"
He lets off an explosion, and Eijirou giggles again and scoots closer to him.
"You know you can ask questions, right? I'm a pretty open book." He rubs his chest thoughtfully. "Remember how I showed everyone my tits before my surgery? Just so they could see the difference?"
"Yeah, and I still think that was a terrible idea. You're lucky Denki didn't beg and plead for you to keep 'em."
"Oh, please. Denki forgot I even had tits to get rid of in the first place." He grins. "My point is, though: ask away. 'M not shy."
"That's an understatement."
He looks to the side. Picks a piece of lint off his sock. Chews the dead skin off of his bottom lip. And then he speaks.
"... Did you do anything different? For that to happen so fast?"
"I got my dosage heightened again, but this is the first time the change has been so drastic." He clicks his tongue. "I guess I also noticed- Wait, how TMI should I be?"
Katsuki swallows. "You're good."
"Cool. So, y'know how you get, like... horny after a T shot?"
Oh, he knows. He spends most afternoons after his shot rubbing his bottom growth raw and bouncing on his dildo until he cries.
"Yeah."
"It was, like, super extreme this time." He whispers. "I was throbbing for days-"
"Okay, too much." Katsuki stops him with a sharp glare, face glowing red. "I get it. You were keyed up."
"Yeah, but that's really the only other difference." He shrugs. "So I guess it's just a high dosage thing. That answer everything?"
No. Katsuki has a million other questions swimming through his head right now, but they're all too embarrassing to share.
"Yeah," he nods. "That does it."
They sit in silence like that for a moment, side by side, staring straight ahead. Katsuki shifts uncomfortably a few times. Eijirou taps his fingers on his knees. Finally-
"So, I was wondering-"
"Have you ever-"
They stop, Katsuki grimacing and Eijirou laughing. The redhead pats him.
"You go first."
"It's stupid," he shakes his head. "Forget about it, you go."
"I guarantee you mine is stupider," Eijirou counters, actually looking a bit sheepish for once. Katsuki bristles.
Bet not.
"Just say it, hair for brains."
"I was.. just wondering," he starts again, pausing to clear his throat. "If- If we could, uh... I mean if you wanted to, like... compare?"
...
"What?"
"Sorry! Stupid idea, see? I told you! Just forget I said anything!" Eijirou rushes, face burning pink. He waves his hands frantically at Katsuki, sputtering more excuses. "I just thought- I-I mean I wasn't trying to- Obviously that's weird-"
"Eijirou, fucking breathe." Katsuki punches his back. "I'm not upset, holy shit. It just caught me off guard."
"I'm sorry," he groans, wincing. "I shouldn't have said anything."
"I..."
Katsuki stops himself.
This can be dangerous.
He's never shown anyone... anything. Like, ever. He's barely even kissed anyone, unless you count him very shyly pressing his closed lips against Hanta's during truth or dare one time last year. And he's not entirely sure that the first time he'll ever present his junk to someone should be over comparing bottom growth with his best friend.
And, yet.
"... Let me lock my door," he says, getting up to do as much. When he turns back around, his legs are shaking, but he puts on a brave face.
"You sure you're cool with this?" Eijirou asks, voice quieter than usual.
"Yeah." Katsuki nods. "Let's do it."
Ten minutes later, they're sitting face to face on Katsuki's bed, legs spread. Eijirou is handling himself, spreading his folds in a very clinical manner while he talks about the differences in texture and sensation.
Katsuki cannot put his hand anywhere near his dick right now, because he is so fucking turned on.
It's honestly a miracle that he isn't forming a puddle of arousal on the comforter right now, because every word Eijirou utters has him clenching down around nothing. He's surprised he's not twitching with need, given how fucking horny he feels.
"And it's a little harder to get, like, wet. What about you?"
Fuck. Eijirou's done, which means it's Katsuki's turn to discuss, and how the fuck are they having a conversation about this right now like it's so casual to lay around ass-naked with your best friend?
He feels like he's going to explode.
"Um. I guess I haven't had a lot of changes."
He leans back a little to try and show off his tiny t-dick. It's semi-hard right now, which makes it a little more impressive, but he hopes Eijirou just doesn't notice.
"The biggest thing for me was obviously my voice and body hair. I used to have blonde pubes, actually." He absentmindedly runs his nails over the trimmed black patch on his mound. "Obviously my clit got bigger, too, but it stopped a while ago. I'm not upset about it, I don't really have a lot of bottom dysphoria."
Eijirou nods, clearly listening intently as he watches the motion of Katsuki's fingers.
"It's... not hard for me to.. get wet." He says it quickly, not wanting to dwell on the subject. "Um, it's also.. kinda easier to stand while taking a piss? I mean, I'm still not great at aiming, but... yeah."
"Sick." Eijirou hasn't looked away from his crotch yet. "You're still pretty big. In my opinion."
"It's not usually-" Katsuki bites his tongue and grunts to stop himself from saying more. Fucking embarrassing. "Thanks. I guess."
Eijirou still isn't looking away. Katsuki sees his throat bob as he swallows. He watches as Eijirou's hand moves to cup over his sex, pointlessly hiding himself.
"... Hey, Katsuki?" He finally looks up, cheeks flushed and brows knit.
"What?" Katsuki breathes, absolutely transfixed by the face he's making.
"What were you going to ask earlier?"
Katsuki feels himself blush impossibly harder. "Nothing. It's not important."
"I know, but..." Eijirou whispers, scooting closer to him. Their knees touch. Katsuki swallows so hard his throat clicks. "... tell me."
".. Have you ever.. fucked someone?" He asks hesitantly, heart thrumming in his chest. Eijirou licks his lips.
"Kinda. Not really. Mina and I went down on each other once, but it didn't really count for much. Barely had a dick, then."
"You do now," Katsuki says lowly. Eijirou nods.
"Yeah. I do." His gaze falls to Katsuki's crotch. "Have you?"
"No. I'm not a hormonal sex pest like the rest of you."
"Ouch." Eijirou snorts. He widens his legs and scoots even closer. His thighs are on either side of Katsuki's. "Are you saving yourself for someone special?"
"That's stupid," he says quietly. "I've just never... wanted to."
"Never?" He asks.
His hand comes away from his crotch. He leans forward, placing one hand on Katsuki's leg. He trembles under his touch, gasping ever so slightly.
"Stop it," he grunts, but makes no move to put an end to Eijirou's advances.
"Why?" He asks. "You don't want anything to happen here?"
"... You're fucking with me, and I don't like it." He clenches his jaw. "Quit it."
"Katsuki, I want to have sex with you," he says bluntly, cheeks flushed pink. "Do you want to have sex with me?"
"You're such a freak," he hisses.
"Yes or no?"
"... Yes."
"Awesome. I'm gonna kiss you now."
Katsuki gets to have one full millisecond of anxiety before Eijirou is on him, sloppily mashing their lips together and guiding him down so he can hover over him while he kisses and fondles him into the bed.
It's way better than Katsuki's first kiss- Hanta was giggly and awkward and fairly stoned, and Katsuki was too inexperienced and nervous to open his mouth. Also, all of their friends were watching and commentating. Denki lost money for betting that Katsuki wouldn't go through with it.
This is... wow.
He feels himself gasping for breath every once in a while, lost so intensely in the passion and heat that he's forgetting to supply air to his lungs.
Eijirou kisses messily. There's a lot of teeth, a lot of tongue. Katsuki no longer has a single unexplored part of his mouth, and he loves it. He's already losing focus enough to let out soft moans every now and then. He feels drunk, like little buzzes of pleasure keep shocking him and the air tastes sweet and he's floating through the sky and-
"Ah-" He gasps, arching when Eijirou squeezes his chest.
"Sorry," he mumbles against his lips. "That okay?"
"Don't be so.. rough with it," he says. "It's a tit, not a goddamn stress ball."
"Sensitive?" Eijirou asks with a teasing lilt to his voice. Katsuki kicks him in the calf. "Sorry, sorry, I'll stop."
Katsuki is sensitive though, especially in his chest, which means he can't stop squirming and gasping out little noises under Eijirou and it's embarrassing, he's never been this turned on and all they're doing is making out. He has to keep reminding himself not to grind up against his friend or moan wantonly because he wants to, he wants to so bad-
"Kats'ki," Eijirou slurs against his mouth suddenly, tightening his grip on his shirt. "You're so hot. 'm so hard right now."
"Yeah," Katsuki agrees, because he's a little too horny to say much else right now. It's nice reassurance to have, though. At least Eijirou's just as dick-stupid as he is right now.
"I wanna..." He leans down and pushes his forehead into Katsuki's neck, hot puffs of air tickling his skin. "Wanna fuck you, Kat."
"I know," he whispers, threading his fingers in Eijirou's hair- which, side note, kinda makes his heart flutter.
"Can-"
"Yeah, fuck, do it." He lets his legs fall open further, sliding his hands down Eijirou's back.
"Is this- ah." Eijirou winces, and his grip gets impossibly tighter. Katsuki can feel the indents from his fingernails in his skin. "Sure this is okay? Not gonna make things weird?"
"It's too fucking late for that." He wraps his legs around Eijirou's hips and pulls him in. "Just fuck me already, Ei."
"Okay. Okay, yeah, I'm just gonna..."
He clears his throat and adjusts them to a more realistic position. Katsuki's legs go back to their original position on top of his thighs, and Eijirou sits up and rests on one extended arm, using his other to guide Katsuki's hips up towards his. Their wet pussies meet for the first time, and they simultaneously shudder. Katsuki's back arches, and Eijirou takes a deep breath.
"Jesus," he whispers. Katsuki moans in agreement. "I-I'm gonna put it in now."
Katsuki wants to say 'I don't need a goddamn play-by-play,' but then Eijirou's very stiff dick is pushing against his slick hole, and he melts into a puddle of horny bliss.
Eijirou keens, pitching forward and subsequently fucking into him, which makes Katsuki sob in pleasure.
"I'm- I can't- Fuck," Eijirou groans. "Feels too good, I have to move fast, I can't-"
"Do it, do it, please," Katsuki begs, slapping his side desperately. "Fuck me hard, Eiji-rou!"
Eijirou starts to jackhammer into him, hips moving of their own accord, selfishly chasing after the white-hot pleasure against his cock. He loses himself in the sensation, trying to simultaneously race to the peak of this feeling and drink in the absolutely perfect sight of Katsuki coming undone beneath him.
He whines and sobs and hiccups and moans, writhing and squirming through it. He clearly wasn't lying about not having a hard time getting wet, because he's so soaked that Eijirou can feel it sticking to his own thighs. He caught on to how sensitive he was while they were kissing but this is ridiculous, he looks like something out of Eijirou's wet dreams.
Katsuki suddenly plants his feet into the mattress hard, digging his nails into Eijirou's waist and grinding up against him while groaning through clenched teeth, and..
Eijirou pauses for a second.
"... Did you just-"
"No," Katsuki denies, but his thighs are shaking and his heart is beating so hard that Eijirou can see the veins in his neck.
"Shit, dude," he whimpers, losing his balance and collapsing on top of him.
Katsuki opens his mouth to complain but doesn't even get the opportunity before Eijirou is grabbing fistfuls of his torso and fucking into him with a newfound fervor. He's helpless to do anything but gasp and cry and let his feet bounce while Eijirou wreaks havoc on his poor, abused hole.
Lips meet the skin of his neck again, but this time there's a graze of something razor-sharp, and he whines loudly, nodding his permission before Eijirou even dares to ask.
Teeth sink into his flesh and he comes undone, trembling and moaning unabashedly as Eijirou goes faster, harder, faster, faster faster fasterfastfastfast-
"Katsuki," he sobs against his skin, kissing the bite marks before he buries his face there and-
"If you don't come in me I think I'm gonna cry," Katsuki admits shakily, clenching around his dick.
That's all Eijirou needs.
Katsuki drinks in every second of his orgasm- there's a quiet squelching noise following by a high-pitched moan from Eijirou. He shudders violently once, twice, three times, and then Katsuki feels a rush of slick against his ass as Eijirou collapses on top of him. They pant against each other for a second, Eijirou still bleary from coming so hard, before he sits up and pats Katsuki's thigh.
"Can I eat you out?"
"What?" Katsuki asks, dazed.
"You didn't finish at the end, right?" He spreads his legs and uses his thumb to pull Katsuki's lips apart. "You're all worked up down here. I can see you throbbing."
"Quit saying 'throbbing,'" he complains, grimacing.
"Alright, my bad," he chuckles. "Can I, though? I really want to. I can make you come so hard, I promise. I've had nothing but good reviews."
Katsuki bites his tongue to keep from calling bullshit considering the fact that he knows Eijirou has only done this once, because just the thought of having that eager mouth on his dick is enough to have him baring down against nothing.
He nods.
Eijirou grins and dives between his legs.
At dinner, Katsuki is uncharacteristically polite. He keeps smiling to himself and bumping knees with Eijirou under the table and he doesn't even yell when Denki reaches over and steals a bun off of his plate.
Eijirou, for what it's worth, is less obvious only because he already acts like an excited puppy most of the time. No one bats an eye at his face-splitting grin or the way he jumps in his seat every time Katsuki glances at him.
No one, except for Mina.
"What's going on with you two?" She whispers lowly. "I've never seen you this calm, Bakubabe."
"Fuck off, 'm acting perfectly normal," he snaps. Eijirou breathes a nervous laugh.
"Yeah, we're fine! What do you mean?"
Her eyes narrow.
"... Congratulations," she says coolly. "But I'm super offended that you didn't tell me."
"Huh?" Eijirou asks, brow furrowing.
"Your breath smells like pussy, and you have a painfully obvious bite mark." She points to Katsuki's neck. "I'm happy for you, but when were you gonna tell me that you two got together?! I've been sooo invested in your tension. Give a girl a win!"
"U-Uh..." Eijirou turns bright red and looks away. "That's, um. We haven't..."
Katsuki buries his face in his hands. "Kill me."
"Oh! My bad, y'all." She covers her mouth and giggles. "I thought... Well, never mind. Enjoy your post-sex carbs."
"I'm literally going to murder you and then myself," Katsuki groans into his palms.
"I could die," Eijirou agrees, staring blankly at the table and nodding. "That works."
"Stop being so dramatic," she teases. "I'm not judging. Don't have any room to anyways, right Ei?"
She winks at Eijirou, who looks like he might just combust into flames. Katsuki suddenly stands and grabs him by the collar, dragging him away and out of the cafeteria.
"Kat- Dude, ow! What's going on?" He manages to wriggle away and hopefully stop the blonde from strangling him with his own shirt and dragging his lifeless body around campus. "Did Mina upset you? I can talk with her, it's none of her business and I don't want her being an asshole to you."
"I don't give a fuck what she thinks." Katsuki rolls his eyes. "I'm just jealous of her."
"Jealous? Of Mina?! Bro, we didn't even really do much-"
"She got to suck your dick," he snaps. "And I didn't. So we're going back to the dorms and you're going to teach me how to give head as good as you do."
Eijirou turns bright red. "Yeah. Okay, yeah, I can do that."