If there was one thing Katsuki knew about Izuku Midoriya, it was that when he got something he wanted, he never let it go. When he was a child, he happily scarfed down his favorite foods. When he was older, school work with high marks hung proudly on his refrigerator. As an adult, his collection of All Might comics and merchandise was meticulously displayed in a glass case in his dorm room. Katsuki knew this, and he was glad for it.
Recently, Izuku Midoriya finally got something he’d wanted for a long time, and Katsuki had gotten something he’d wanted for even longer.
As Izuku sat beside him, rambling incoherent babble about…something Katsuki had bullshited about being bad at—physics, maybe—he stared a deep, heated gaze into the purple mark on his neck. It was mostly covered by Izuku’s shirt collar, which had been popped up in that suspicious way that told everyone who saw him, ‘please don’t look at my neck because I have a massive hickey from when I got a little too wild a few nights ago.’ Which he did, and it was a few nights too many for Katsuki’s liking.
After their last “study session,” Izuku had only replied to Katsuki’s many, many texts after he’d complained about getting a low grade on a test. This, of course, was a lie, but for some reason, Izuku didn’t seem to want to talk about anything that happened that day. The day Katsuki had dubbed as—so far—the best fucking day of his life. Apparently Izuku did not feel the same way.
But that couldn’t be right. Izuku had wanted it. He’d wanted it bad. And now that he’d gotten it, he should have been coming over every day to spread his cheeks and sit on Katsuki’s cock, moaning about how much he loved having “Kacchan’s” dick up his ass.
That was what should have been happening.
Instead, Izuku tapped his mechanical pencil against Katsuki’s textbook in an irritated way, and sighed, “Kacchan, you’re not even listening to me, are you?”
“Sorry,” Katsuki grumbled facetiously. “Did you say something?”
Izuku closed the book, a loud thwap echoing from its pages. His eyes narrowed. “If you aren’t going to take this seriously, then I’ll just leave.”
“I could say the same thing.”
Katsuki watched as Izuku’s brow twitched for a moment.
“What…” Izuku cleared his throat. “What do you mean?”
“Oh, come off it,” Katsuki growled, grabbing Izuku’s shirt to pull down his collar. “I’m talking about this, Deku.”
The freckles on Izuku’s cheeks receded behind the eruption of red on his face. It wasn’t just one. When Katsuki ripped open the top button, he revealed an abstract collage of bite marks and hickeys, now deep shades that had settled into his skin.
Izuku stammered, frozen in place, “I—that’s—it’s not—”
“Close your mouth,” Katsuki griped. “You look like a damn fish.”
Izuku’s lips shut immediately. Katsuki reached a hand out, cradling his kiss-stained neck, dipping down to caress his collarbone. Izuku tensed and rolled his shoulders forward, glancing at everything in the bedroom but Katsuki.
“Listen up, Deku.” Katsuki stood, dragging Izuku up with him. He ignored the guilty look etched across his face. “Stop treating me like I didn’t want this. I started this shit, not you. ”
His hand curled into the fabric of Izuku’s shirt as he pulled him closer. Izuku let out a startled noise, his eyes flickering to Katsuki’s lips as he spoke.
“I fucked you. So stop acting like you committed a crime or some shit,” he snarled.
Izuku swallowed, looking down. “I… Technically, I did…”
“Yeah, fine, technically . Fuckin’ nerd…” Katsuki rolled his eyes. “But the only ones who know about this are you and me. And I wanted it. You wanted it.”
His grip loosened as he stepped forward, slipping a knee between Izuku’s legs. He felt a gentle, telltale throb against his sweatpants.
“You still want it, don’t you?” he whispered, fingers dancing across the column of buttons that barred him from Izuku’s chest. He heard a quiet gasp and a hitch of breath.
Katsuki glanced at Izuku’s mouth, soft and pink, parted ever so slightly, inviting him in. He wet his own lips in anticipation, leaning in to let his words brush against Izuku’s jaw.
“Tell me you want me, Deku,” he said with a smile. Izuku jolted upright when Katsuki pressed their lips together, murmuring into his mouth, “I know you do.”
The kiss was slow and moist and soft. Softer than Katsuki remembered. It had been too long. Only a few days, but it was enough time for him to forget how warm Izuku’s tongue felt as it glided against his own, how Izuku’s whimpers buzzed down his throat when he swallowed. He drank Izuku in like a fine wine, like a cup filled with the sweetest ambrosial essence.
When Katsuki pulled back, he observed the way Izuku’s eyelashes fluttered with every gasping breath he took. His hands trembled, clutching nervously at the hem of Katsuki’s black tank top.
“I…” he started, barely a sound. His round eyes glistened with an unmistakable need. “I…want you…”
Katsuki threw everything on the top of his desk onto the floor. He grasped Izuku by the waist, and turned him over, tossing his back onto the desk’s surface. Izuku squeaked, looking up at Katsuki as he hovered over his figure.
“There he is,” Katsuki chimed, slowly pulling down the zipper of Izuku’s pants. “There’s my slutty Deku.”
His thumbs hooked around Izuku’s belt loops as he tugged them down, inching his way towards revealing Izuku’s smooth, bulky thighs. When Izuku’s pants dropped onto the carpet, Katsuki grinned, flashing his teeth ominously.
“…Red, huh?” His fingers curved over the prominent bulge under the crimson fabric of Izuku’s boxer briefs. Katsuki purred, “Did you know you were wearing my favorite color, Deku?”
Izuku opened his mouth, but no words came out, cut off by the snap of his waistband when Katsuki pulled the undergarment down his pelvis. He let out a husky laugh as Izuku’s cock bounced against his stomach.
“Did you know that if you came over I’d try to rip these off you?” Katsuki pried, words filled with smug confidence.
“N-no… I didn’t,” Izuku whined, arching his back into Katsuki’s finger, trailing up his abs just beside the length of his cock.
Katsuki hummed in amusement, biting his lip as Izuku shuddered under his touch. “God, you’re so fucking soft. ”
He left Izuku on the desk as he walked to his bedside drawer, taking his time to pick up the same lube he’d used not that long ago. When Katsuki turned around, Izuku had lifted his neck to gaze at him like a lost kitten waiting for his master to return. Perfect. Perfect.
“So you want me…right, Deku?” Katsuki asked, waving the container in his hand as he returned to the desk. He placed himself between Izuku’s legs once more, and shoved him back down. “Then just relax and let me take you.”
Izuku shivered, raising his hand and biting his knuckles. He nodded, still not saying a word. Katsuki quirked his brow. I’ll have to fix that, he thought, parting Izuku’s shirt after unfastening the rest of his buttons.
Once again, he bathed in the sight of Izuku’s naked body. Izuku’s body. A body he’d watched his whole life. One he’d watched grow from a scrawny stick that could barely toss a tennis ball to a mass of lean, defined muscle that could easily keep up with Katsuki on the basketball court at the park behind his house.
Izuku was soft, but strong. His figure was built and sinewy, yet sensitive and tender. Any baby fat he’d gathered as a child was gone, replaced by something Katsuki could only describe as hard and raw. Something that turned Izuku from a boy to a man. Something that Katsuki wanted to have and hold and keep all to himself because it was his. Izuku was his.
Izuku… All soft skin and taut muscle, pillowy lips and hard nipples. Striking abs and pecs, thick arms and legs, a well-shaped, well-hung cock that weeped for Katsuki to bury himself inside his warm, velvety hole. Katsuki ran a hand through his hair, feeling the sweat on his brow the same as he would on Izuku’s. He swallowed thickly to relieve his dry throat, and placed his hands on Izuku’s thighs.
“Feels so good looking down at you like this,” he hissed, gently pushing on Izuku’s legs to urge them apart. “Spread yourself nice and pretty for me, Deku. There we go…”
He was panting already, looking up at Katsuki like a man starved by his own lust. His chest rose and fell in heavy waves that cascaded peaks of desire in Katsuki’s eyes.
He sucked in a breath, and reached out towards Izuku’s body. As Katsuki’s fingertips glided along his skin, Izuku shut his eyes and arched into him once again.
“Fuck, when did you get so big?” Katsuki sighed, splaying his palm across Izuku’s chest. “Remember when you were half this size? When I would climb into your lap, shove a book in your face, and tell you to read it to me…”
Izuku quivered under his fingers, biting his lip as a refusal to speak. Katsuki smirked, his digits twisting around Izuku’s pert, darkened nipple.
“All those times during the summer we sat beside the pool eating popsicles…” He wet his lips, listening to Izuku’s pitiful squeak. “…And we competed to see who could shove the most in our mouths at once?”
Big, green eyes, filled with a thin layer of tears, flew open in a sudden, shocking realization. Color drained from Izuku’s face, and Katsuki sneered. He leaned in closer, hissing into his ear, “Remember that, Deku? How it dripped down our shirts as they melted…”
As his index finger dragged like an iron brand down Izuku’s torso, Katsuki could feel his skin heating beneath its touch. He chuckled, smug and spiteful.
“Remember how I always won? ”
“A-ahh!” Izuku cried out as Katsuki’s hand wrapped around his cock. His arms rose above his head, gripping the edge of the desk behind him. “Ka—Kacchan…!”
“Don’t bust your nut yet, nerd,” Katsuki laughed, slicking his other fingers with lube. “We’re just getting started.”
One by one, he slid them inside, soon rocking his hand at a steady pace. Izuku’s eyes strained to stay open, to gaze at Katsuki’s face while his fingers slapped against his ass. Katsuki noticed the shame, the hunger that carried in the look he gave. He swiped his tongue across his upper lip, and smirked.
“You thinking about me sucking you off, Deku?” he asked, holding back a chuckle when Izuku’s face paled again. “Thinking about my lips against your prick? It’d be nice, right? I’d hold you down while you fuck my mouth…”
Katsuki ignored his stammering, and leaned in to whisper into his ear.
“You’d like that, wouldn’t you, Deku? You want my sloppy tongue around your fat, nasty cock? ”
He punctuated his last word by twisting his fingers deeper. Izuku convulsed, and craned his neck.
“Oh God, Kacchan…! Kacchan! ” he moaned, clawing feverishly at the surface of the desk.
Katsuki groaned, letting go of Izuku’s cock to pull down his sweatpants and free his own. He began stroking a generous amount of lube up and down its length.
“I’d do it,” he said, heaving his weight forward into Izuku, curling and spreading his fingers. “I’d do it so fast… Make you cry for me like the desperate slut you are.”
“Yes… Yes, please …” Izuku whimpered when Katsuki’s hand left him, replaced by the tip of his cock pressing against his hole.
Katsuki took a deep breath, and pushed in.
They both raised their heads as they moaned together, Katsuki’s long and guttural, Izuku’s loud and wavering. Blunt nails dug into Izuku’s thighs as Katsuki’s dragged him further down onto his dick.
“Fuuuck, you’re so fucking tight. ” Katsuki could feel the ring of muscle clench harder around his girth. Izuku twitched and shivered, rolling his shoulders as he squirmed under Katsuki’s hold.
When Katsuki decided he had sufficiently stuffed Izuku full of cock, he took a moment to pull back, and then started to thrust. He made sure his pace was painfully slow, just so Izuku wouldn’t cum before he could count to ten. His tip was already dripping, and his face was flushed and red. A blissful, fuck-out haze clouded his eyes. Katsuki couldn’t stop himself from giving one good, powerful jerk of his hips.
Izuku gasped, “ Ah, K-Kaccha—Katsuki…!”
His hands slammed down on the desk, palms splayed on either side Izuku’s head. Katsuki licked a warm trail along the length of his neck, and growled.
“Yeah, that’s right… Say my fucking name.”
Their foreheads pressed together as Katsuki began slapping his hips deeper into Izuku. He inhaled every choked breath that tumbled from Izuku’s mouth, sobbing his name like he was about to vanish from the world.
“Katsuki… Katsuki, Katsuki …”
He devoured Izuku’s soft, soft lips in a thunderclap of a kiss that rumbled their moans through every inch of their bodies. Katsuki grinned as he pulled away, feeling the thin trail of spit he’d left between their tongues.
He ran a hand through Izuku’s sweat-drenched bangs, and purred in his ear, “Say my name like you do when you jerk your dick at night.”
Izuku arched, voice torn and cracking, dead before it passed his lips. He let out a broken cry, dragging his fingers down Katsuki’s back. Tears started to peek from behind his closed eyes. Izuku wailed his name once more.
“ Ka …tsuki!”
He smirked complacently. “You think of me when you touch yourself, Deku? Bet you do… Bet you think of me squeezed between your legs just like this.”
Katsuki stroked the curve of Izuku’s ass before pinching his skin. Izuku jolted, causing Katsuki’s cock to suddenly change its angle. He bit his lip and keened, his grip fading as he swayed in a pleasure-filled daze.
Izuku mumbled, stumbling over his words, “I… I think…of—”
“D’you touch yourself in the dorm while your roommate sleeps next to you? Don’t fucking lie to me. ”
Katsuki twisted his hips, and Izuku moaned, “Y-yes, yes, I do…Kacchan…”
“God, fuck, I knew it,” he laughed darkly, placing his hands above Izuku’s hips. “Shit… What would he do if he knew you were whacking it to a high school kid?”
For a moment, Katsuki slowed, his cock grinding to an unbearable pace. Izuku peered up at him in confusion, observing the way his lips curled into a malicious smile.
“No…wait,” Katsuki uttered, dangerously quiet. “You said since I was fifteen , right?”
Izuku gasped as Katsuki yanked on his waist, thrusting his hips deeper, deeper into his thighs. A scream caught in his throat when Katsuki’s cock slid against his sweet spot.
“What would he do if he knew you were thinking about a middle school kid? ”
A wet trail rolled down Izuku’s freckles as he writhed and sniffed, “Th-that’s not—I didn’t—”
“Don’t deny it, you piece of shit. You thought about fucking a damn middle school student, didn’t you?” Katsuki chided, thumbing at Izuku’s tears to stop their tracks.
When Izuku said nothing and only whined pathetically, Katsuki grabbed his chin.
“Fucking answer me, goddammit.”
Izuku’s eyes widened as Katsuki tilted his head up. He stared back into them, and they shared a look. Katsuki paused.
“Holy shit, Deku.” His heart raced. He quivered excitedly. “You thinkin’ about it right now?”
Izuku remained silent, but his face flushed. Katsuki’s mouth twitched into a crooked grin.
“You are, aren’t you?” he laughed, picking up his pace, slapping his hips faster. “Picturing it in your head? Two years ago I was a little smaller, hadn’t beefed up as much…”
“A-aah…ah…!” Izuku gasped at his words, nails dragging on the desk beneath him. Katsuki grabbed his hands and pinned them over his head.
“But you still wanted this, right? You wanted my teenage prick in your ass,” he breathed, weighted and heavy.
“K-Kacchan, p-pl- please …” Izuku wailed, rocking his hips up into Katsuki’s.
He licked his lips. “ God , say it, Deku. Say you wanted this dick.”
“I…” Izuku wavered, panting and heaving with every powerful thrust. “I-I…”
Katsuki pounded into his spot.
“Say you wanted my thick, virgin cock to fuck your slutty hole… Wanted to ride this dick ’til I never thought of a girl ever again.”
“I—I did…! ” Izuku screamed. “I th-thought about you…whenever we s-studied together… I thought about—about being your f-first… I w-wanted… I wanted you all to myself…!”
Izuku tensed. Katsuki’s smile had vanished.
His fingers threaded with Izuku’s as he leaned over, burying his face in the crook of his neck.
“You’re fucking disgusting,” Katsuki grunted, squeezing Izuku’s hands. His breath came out in harsh, thick pants. “Deku… Woulda fucked you so hard… Woulda fucked you ’til you cried, ’til you screamed, fuck, I wanted to rip your ass apart so bad …”
He heard Izuku whimper in the back of his throat, and his hands squeezed back.
“Kacchan…” Izuku’s voice trembled. “Katsuki…”
“Izuku, I’ve—” Katsuki paused to swallow down the air between them. “I’ve wanted to fuck you on this desk ever since I knew what it meant. ”
Izuku cried out, arching his back. His legs went limp against’s Katsuki’s rough, unrelenting pace, and his mouth watered as hung open.
Katsuki kissed under his jaw, his chin, down his collarbone with every precise, calculated jerk of his hips. He licked up Izuku’s tears as they fell, surprised by how sweet they tasted, but why wouldn’t they be? They were Izuku’s. Everything about him was perfect.
From the way he looked, the way he sounded, the way he acted, the way he kissed, the way he cried, they way he lusted after Katsuki because Izuku was his , and so was he. He was Izuku’s . And if there was one thing Katsuki knew about Izuku Midoriya, it was that when he got something he wanted, he never let it go.
“Katsuki…!” Izuku’s hands tightened around his. “Katsuki, I-I’m…!”
“Yeah, fuck, fuck, ” he groaned, pressing their chests together. “Cum for me, cum for me, Izuku… Tell me who it is that’s fucking you.”
“Katsuki, Katsuki!” Izuku twitched, clenching his muscles around him one last time. “Katsuki, oh, Katsuki… Katsuki! ”
His cum shot between their stomachs in several short bursts. Each time, Katsuki thrust harder and harder into his tight, squelching hole. As he gazed down at Izuku’s blissed-out face, and the moist sounds of his cock slapping in Izuku’s ass rang through his ears, Katsuki knew it was over for him.
“Shit, shit, shit, Deku…! Izuku! ”
With that, he was finished, finally claiming Izuku as his for a second time.
In the aftermath, he fell on top of Izuku's slackened body, hot and sweaty as they both caught their breath. Izuku let out a deep sigh, running his fingers through his damp hair.
“Wow…damn…” Katsuki panted. “I think that’s the first time I’ve heard you say ‘fuck’ without me telling you to…”
“Because I try to be a good example for you,” Izuku said, pursing his lips as he glanced at Katsuki. “That apparently didn’t work.”
Katsuki grinned, nuzzling his face under Izuku's chin like a cat, almost purring in satisfaction. A hand rested on the top of his head, and Izuku twirled mindless patterns in Katsuki's hair.
He murmured, “Kacchan… This is really dangerous, you know?”
“We… I would get in a lot of trouble if anyone finds out.”
Izuku stopped his motions. “I’m serious.”
“So am I.” Katsuki propped himself up, hovering over Izuku where he lay on the desk. “Deku. I’ve never been more serious than when it comes to you.”
Izuku flushed, shrinking into himself. “…You mean that?”
“ ’Course I do,” Katsuki mumbled against his lips before capturing them in another slow, passionate kiss.
When he pulled back, Izuku gazed up at him with shimmering eyes. “Stop… Stop making me fall for you even more…”
“Ahh, who cares?” Katsuki reached out to ruffle his bangs. “In about a year, no one’s gonna give a shit, anyway.”
Izuku attempted to push his hand away in protest, but Katsuki grabbed his wrist first. He turned it over, and pressed a gentle kiss to Izuku's palm.
“Maybe then I’ll take you on a date or something.”
Izuku frowned. “After a year of this is when you’ll take me on a date? How charming…”
“Shut up,” Katsuki grumbled. “You love it.”
“I…do.” Izuku slipped out of Katsuki's hold, and tenderly caressed the sides of his face. As he looked up at him, he smiled. “I really do.”
“Fuck yeah, you do.”
Izuku giggled as Katsuki kissed the sensitive spot behind his ear. They both held each other for a moment, content to have and to be had by someone they’d wanted for so long. And it was perfect.
Katsuki sat up, breaking the silence.
“You know…I still have my middle school uniform. Might be a little tight, but I bet I could fit into it.” His lips turned upright. “You want me to put it on next time?”
Izuku nearly burst every vein in his body as blood rushed to his head. Katsuki laughed uproariously.
“You’re…dangerous,” Izuku mumbled, covering his mouth. “Way too dangerous.”
“That’s your dumbass nerd way of saying ‘yes,’ right?”
Izuku glanced at him, and nodded.