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Katsuki had never been more mortified in his entire life. It was just supposed to be a quickie to take the edge off after a particularly riveting battle against a villain. Something about Izuku using the iron suit Katsuki had paid for, especially getting to see those thigh muscles in action and the mock up of black whip had him so hot and bothered. The adrenaline and nitroglycerin running through his veins, speeding up his heart probably assisted but getting to see Izuku take the villain down, a foot in the guy’s back and black whip yanked up tight to subdue the guy, really had Katsuki shifting his weight. Izuku’s scent, thick with exhilaration and excitement, had Katsuki blushing and burying his face in his high collar.
It was taking far too long for the police to finish their reports for Katsuki’s comfort. He stomped his foot like a child and his scent was sour with impatience. Izuku kept glancing over his shoulder at him, concern etched in his face. Katsuki glared right back over his high collar. When the police and reporters finally let them free, Izuku approached Katsuki like a kicked puppy.
“Are you mad at me, Kacchan?” Izuku asked sheepishly.
“Idiot,” Katsuki growled as he grabbed Izuku by the wrist and dragged him into a dark alleyway. He pushed Izuku against the wall by his belt and smashed his mouth against his.
Izuku moaned and Katsuki used it to lick his way into Izuku’s mouth. He fumbled with the belt, looking for the button he’d hidden secretly in the design of the belt to release the lower half of the iron suit. Sue him. He had needs of his own that only his alpha could provide him.
“Ka-Kacchan, we’re in public…”
“Shut up. It’s private enough,” Katsuki purred against Izuku’s neck. “You looked so…sexy in that fight today, Deku.”
Izuku whimpered a bit at the attention. “You’re always sexy when you fight, Dynamight…”
Katsuki found the button and pressed it as he grinned up at Izuku with his fangs on display. “Put your words to good use, hero. Fuck me like you fought today.”
Izuku panted and leaned his head against Katsuki’s. “I want to. I want to so badly, mate. Please let me.” His mouth watered and his saliva dripped down larger fangs as he panted. “Let me fuck you, Kacchan…”
Katsuki, satisfied with Izuku’s begging, dropped his baggy pants to his ankles. “Come get it then, alpha.”
Izuku grabbed Katsuki around the hips and turned them so Katsuki was holding himself up on the wall with his arms. Izuku studied him, rubbing bruising circles into Katsuki’s plush hips. Katsuki’s leotard barely covered his pretty pussy and Izuku’s mind was spinning at the sight of it straining against the fabric. He shoved the strip of fabric aside and groaned at the wetness there. He kneeled on the cement and sniffed the fabric.
“Taking your time, huh?” Katsuki complained, looking over his shoulder.
Izuku responded by licking him from front to back. Katsuki shuttered as Izuku licked him clean of any slick. He then put two fingers in his mouth, wetting them thoroughly while he continued to rub Katsuki’s hip with his other hand, before plunging them one by one inside. Katsuki moaned loudly, pressing his forehead against the bricks. He was so dazed by the thick rough fingers inside him he didn’t notice black whip twining up his leg. It branched at his hips, one tendril joining the fingers and the other wrapping around his mouth like a gag. He tried to clench his teeth around it as he drooled and moaned messily around it.
“You’re taking this all so good, Kacchan, but you can’t make all that noise for just anybody to hear,” Izuku cooed. He stood up, keeping his fingers and black whip inside, curling and twisting to make Katsuki’s legs shake. “You wanted me to fuck you like I fought today. So I’m gonna do just that, mate,” he growled dangerously in Katsuki’s ear as he leaned his weight against his back.
Katsuki pressed his knees together to keep himself upright as Izuku worked him with his fingers. He tried to rock himself down, wanting more more more, but his thigh muscles quivered too much. The black whip plunged inside him snaked out with a wet pop before coming up to bind Katsuki’s wrists together behind his back, leaving his face on the wall and Izuku’s hands to hold him up. He whined as Izuku slowly pulled his fingers out, scratching his soft walls with his nails. Katsuki mashed at the gag, wanting to beg for more. All he could do is whimper and stink up the whole alley with his slick and his scent. Izuku lapped it all up, licking his fingers like he was cleaning them after a good meal. When he was satisfied he’d tasted all of Katsuki, he used his wet fingers to slick up his heavy hard cock. Katsuki whimpered in anticipation.
Izuku took his time, pumping himself calmly as he looked at the work he’d done. “Haven’t marked you up enough. How will anybody know you’re mine? You could just be some slut on the street.” He leaned forward and started sucking bruises into Katsuki’s porcelain skin on his broad shoulders and neck. “Let’s remedy that, shall we, mate?”
Katsuki cried out against his restraints when Izuku bit down hard enough to draw blood at the juncture of his neck and shoulder as he plunged his cock deep into his pussy, all the way to the base. The stretch and pain were barely noticeable around the ecstasy and pleasure that rattled Katsuki’s very soul as Izuku pounded into him relentlessly. He would pull out all the way to the tip just to thrust back in to the base. Tears streamed down Katsuki’s cheeks as his eyes rolled to the back of his head. He was getting exactly what he’d wanted. He moved his head slightly down and watched his own tits bounce, hitting the wall as he was rocked forward and back. He swallowed tightly as Izuku’s hands came around and cupped them so tightly his flesh pushed between his fingers. Just the sight of Izuku’s possessiveness had him drooling. He was sure he’d already came once or twice but his mind was so deep in the clouds he couldn’t really tell. He was simply a rag doll to ba fucked senseless against that wall and he was loving every last minute of it.
Izuku squeezed Katsuki’s chest tight and leaned his head against his back between his shoulders. “Kacchan, I’m gonna come…”
Black whip released its hold on Katsuki, letting his arms free to rest his hands over Izuku’s in his chest and his mouth to drool and babble. “Come inside…it’s okay…”
Izuku nodded against Katsuki’s back. His thrusts lost their steadiness as he coated Katsuki’s insides. He kept thrusting even after the orgasm and something was starting to dawn in Katsuki’s sex idled mind.
“Wait…you’re going to…” he tried to say but it was too late.
Izuku’s knot inflated deep inside him. Katsuki could have sworn he could see his lower belly distend a bit. The realization that they were locked together like that until the knot went down slammed him like a freight train. They were in public and Izuku’s knot notoriously took a million years to release.
“Fuck, Izuku…” he whined, covering his face with his hands. What a PR nightmare.
“I’m so sorry, Kacchan,” Izuku muttered. “I couldn’t help myself. You just taste and smell so good and you’re so sexy when you’re all open for me. It just happened…”
Katsuki sighed and leaned his head against the wall. “No use apologizing now. Just focus on…not knotting thoughts…”
“Okay…”
Katsuki just prayed to any god who would listen that nobody needed that alleyway for the foreseeable future and that his bare ass wouldn’t be on the news in the morning.