baby brother all grown up

Pairing: Shindo/Izuku 

Tags: ABO, Incest, Shindo is Izuku's brother, anal sex, somnophilia, Omega Izuku, Alpha Shindo

Summary: After their parents, Shindo steps up to take care of his younger brother, Izuku. Omega Izuku often crawls into Shindo's bed to get some comfort but one day, when he feels his older brother's Alpha cock rubbing against him, he can't hold himself back 

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There was just some things that, as an Omega, he couldn’t ignore. Snuggled up to Shindo’s chest, his head pleasantly nestled between his prominent, pillowly pecs, Izuku experimentally wiggled his hips, grinding his big brother’s thick, hot cock against his butt. Every breath he pulled in was full of Shindo’s sweet scent. It was still a couple weeks until his heat was supposed to start but as he lay there, breathing in his big brother’s scent, surrounded by his warmth, it felt like he was about to go into heat right there. Turning his head slightly so his face was smooshed against Shindo’s sweaty skin, Izuku let out a slow, shaky breath. There was so much slick leaking out of his hole, the seat of his shorts was soaked. He was so hard, it was nearly painful. Every time he rolled his hips, his cock rubbed against Shindo’s firm belly. Sharp sparks of pleasure raced through his body, giddily whispering an almost desperate need. Gulping hard, Izuku raised his head to peer into his big brother’s face.

Shindo was so used to him coming in and lying on top of him like this, he hadn’t moved at all in his sleep. Izuku was the only one who could come into his room, unexpected, and not get thrown through a wall. Their parents’ deaths had left him paranoid, constantly looking over his shoulder for any signs of danger. He was sure there was never a point when Shindo wasn’t worried about him, before and after their parents died. Thing about being the kids of infamous villains, there were always people – heroes, vigilantes, other villains – who were after them. Though, not that they had to worry much nowadays. Shindo was even more feared than their parents. There weren’t many who would dare go against him, meaning he didn’t have to be so paranoid. He still was, though, and Izuku was certain that he would be for the rest of their lives.

Course, that overprotective streak meant that Izuku could get close like this...without any fear of being caught. Good thing for him, considering that right here was the only place he felt truly safe. Exhaling slowly, Izuku turned his attention back to Shindo’s chest. Their air conditioning had been broken for the past few days. The heat in their apartment was almost unbearable. Shindo’s tanned skin was covered in a thin layer of perspiration. Exhaling slowly, Izuku slipped his tongue out of his mouth to drag it up between his big brother’s pecs, gathering up a mouthful of sweat. An incredible, delicious saltiness filled his mouth. Izuku moaned low in his throat. His cock twitched eagerly against Shindo’s belly. Fuck...this was bad. This was really bad. He was going to go into heat at this rate!

But...that...that was fine...wasn’t it? Izuku’s eyes fluttered open. He exhaled shakily, slowly lifting his head to peer into his brother’s face. Shindo always said he could come to him for anything – no matter how big or small the problem was, he’d do everything in his power to fix it. Well, there was a problem right now. His instincts were being kicked into high drive, riled up by the intoxicating scent of his big brother, by the feel of his heat pressing in all around him. Izuku swallowed hard against the dryness in his throat. He twisted around to get his first look at Shindo’s cock. A flood of drool poured into his mouth at the sight of it. His mind went completely blank, fogged over by a dense, buzzing haze. Sitting up, bracing his hands on Shindo’s beefy chest, Izuku carefully turned around so he was facing that gorgeous erection. He reached out with a trembling hand to brush the tips of his fingers against it. Shindo’s cock twitched. Precum spurted out of the slit. Izuku’s tongue flickered out to run across his bottom lip.

Shindo was so hard. It had to be painful, even if he was only experiencing the agony of this intense arousal in his dreams. As his younger brother, and obviously the cause behind him being so excited, it was only right that he did something to help! Nodding firmly, his mouth pressed into a determined line, Izuku straightened up and bent forward to slip his underwear down just enough to expose his butt. While he knew it would be easier to strip the dumb thing off, he couldn’t bring himself to separate from Shindo right now. If he was devoid of this heat for even a second, he felt like he might die.

Panting heavily, his head swimming with desperate want, Izuku swung back around, bracing his knees on either side of Shindo’s hips. The brush of Shindo’s cock against his ass sent a blazing bolt of pleasure coursing up his spine. Breath catching in his throat, a thin line of drool dribbling down his chin, Izuku raised his hips up, reaching back to lead the head of Shindo’s cock to his slick drenched hole. The tip nudged against him. Izuku whimpered loudly, his body shuddering. Fuck...fuck, fuck, he was going to go crazy and Shindo wasn’t even inside yet! Resting his hands on Shindo’s muscular thighs, Izuku lifted his hips up higher until he was hovering over his cock. He knew he should take it slow since this was his first time but...he couldn’t wait anymore! Inside-! He wanted his big brother’s cock inside him already-! Biting down hard on his bottom lip, Izuku took a couple more seconds to make sure everything was lined up properly before slamming his hips down.

Moving with such vigor ended up being a bad idea. The moment the bulbous head of Shindo’s cock pushed through the tight ring of muscle to sink deep into his hole, he was already overwhelmed with pleasure. By then, his momentum was so great, there was no way for him to stop. He sunk all the way down to the base, taking in every last inch of Shindo’s large, thick cock. Throwing his head back, tongue hanging out of his mouth, Izuku came with a high pitched, strangled whine. Thick ropes of white splattered all over Shindo’s toned, tanned stomach and chest. Panting heavily, his head already swimming, a screech of wild ecstasy tearing through him, Izuku didn’t think twice – not that he could. The pleasure of having his big brother’s thick, hot penis inside him was making it impossible to coherently think anything. All that was going inside of his foggy mind was a constant howl of ‘GOOD! GOOD! BIG BROTHER’S COCK FEELS SO GOOD!’.

Leaning forward, bracing his hands on Shindo’s belly, Izuku began to vigorously bounce on top of him, slamming down against his hips to drive his cock in deep. Every time they collided, he could feel Shindo’s knot pressing insistently against his hole. Slick drenched his thighs, dribbling down to splatter onto Shindo’s legs. Underneath him, his big brother was still asleep but it was obvious that he was feeling good. A sharp blush of red tinged his cheeks. The pace of his breathing had picked up dramatically. His chest heaved with every harsh pant. Whining low in his throat, Izuku dropped down (as carefully as he could) on top of his big brother, pushing his face into the curve of his throat. Good...good, good, good, good! It felt so fucking good! He couldn’t stop his hips! Harder! Deeper! This rhythm felt good but...more...more, more, more!

“Big brother...please...” Izuku whined, slamming his hips down and grinding against him. This...it wasn’t enough! He needed more-! Wanted more-! He...he wanted his big brother to fuck him! Not just lay there still underneath him, the only evidence that he was feeling good being the slightly elevated pace of his breath! He wanted those dark eyes to look up at him teasingly! For him to whisper teasingly as those big hands roamed all over his body, finding all of his sensitive spots and exploiting them until he was begging him to stop! This kind of sex...where he was the only one doing anything...it was infuriating! He could feel himself getting closer to cumming but it was driven by his instincts as an Omega! There was no resisting a thick, hot Alpha cock inside of him!

“Big brother, big brother!” Izuku chanted, the pace of his thrusts becoming jagged and erratic.

In this position, his cock was squished against Shindo’s stomach. Every time he moved, the friction and pressure threatened to send him careening over the edge. Clenching his teeth together, bitterly wishing that it was his big brother’s hand wrapped around his dick, Izuku raised his hips up then slammed down one last time, taking in every inch of Shindo’s cock. An immense blast of harsh, electric pleasure screeched through him, quickly filling up his entire body. White flooded across his vision. He came a second time without a sound, his mouth stretched open in a silent scream. There came a quiet, strangled groan from above him. Muscular arms clamped down around him, crushing him to Shindo’s larger body. Shindo slammed his hips up. His cock swelled up even bigger, stretching him further open. A burst of scalding hot, thick semen poured into him. Izuku’s eyes widened. His tongue hung out of his mouth. A fresh boiling blast of ecstasy slammed into him. His cock twitched violently against Shindo’s stomach as he came a third time. Nothing came out of his cock. His balls burned from the force and magnitude of his orgasm.

Panting raggedly, Shindo’s bedroom spinning lazily around him, Izuku collapsed down onto his big brother. His heat seeped further into him, inching closer and closer to his belly. Swallowing hard, Izuku shakily raised his head just enough to peer at his big brother’s face. Still sleeping. He knew Shindo was a heavy sleeper...but it was astonishing that he had snoozed right through that. Izuku frowned deeply, his bottom lip pushed out in a pout. He sighed, dropping his face back down onto Shindo’s sweaty chest. This wasn’t good. While he didn’t regret what he had just done, simple fact of the matter was...he had done it in a moment of pure heat. Now that he’d gotten a taste of what it felt like to have his big brother’s cock buried deep inside him...he knew he wouldn’t be able to forget.

He knew there was never going to be anyone else for him. No one could make him feel that good by just lying there. It was a little scary...and a lot exciting to wonder what it would feel like to be truly fucked by Shindo.

Izuku shivered. He...he wanted to know. He wanted so badly to know, the temptation to wake Shindo up just to try to convince him to fuck him was nearly impossible to ignore! Sighing again, Izuku snuggled closer to Shindo’s warm, sturdy body. As much as he wanted to do that, the after vigorous sex exhaustion was closing in. Izuku’s eyes fluttered closed. Tomorrow...he would test the waters...see how Shindo reacted to the idea of them being together. Maybe...his overprotectiveness would extend into not wanting to see Izuku mating with another Alpha. Considering how he ferociously he drove any interested Alphas away from him, he felt like he might have a chance!

Sighing softly, Izuku drifted off. Just as he was about to fall asleep, Shindo shifted underneath him. The movement didn’t really catch his attention since he thought that he was trying to get comfortable so he barely registered Shindo lifting his head and pressing a firm kiss to the crown of his head. The most he felt was his muscular arms curling tighter around him. Used to that sort of thing since it happened often, he snuggled even closer, happily rubbing his cheek against Shindo’s smooth, warm skin. His big brother...he loved him so much...he didn’t want to see him claim another Omega. He wanted to be his...his Omega...