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Izuku squirmed in his seat, trying to rid himself from the discomfort.
Why did this kind of thing always happen to him? Some days, he wondered if he did have some sort of quirk that cursed him with this much bad luck. That, or the universe liked to play big cosmic jokes on him. Seriously, who did he kill in a past life to end up with so much bad karma?
It was supposed to be a quick trip to the corner store a few blocks from UA to stock up on some snacks before movie night with his class.
Izuku had seen a woman, hunched over on the street. She was trembling. He tried not to startle her, but clearly he hadn’t tried hard enough, because she started hard. She yelped, a flash of energy flowed through his body, and her eyes widened.
She muttered out an apology, explaining the effects would wear off in a week or so but that her quirk wasn’t dangerous, and she was very sorry. Before Izuku could ask what her quirk was, she bolted.
He’d wanted to run after her, snacks be damned, but he wasn’t sure he could help. He felt fine, and the woman seemed more embarrassed than anything about hitting him with her quirk, so he figured she must be telling the truth about its effects not being dangerous. Besides, he didn’t want to get her in trouble for illegal quirk usage. It was an accident.
He’d kept the fact that he’d been hit by her quirk a secret.
The ache in his chest had been steadily developing since last night, growing heavier as the day progressed. He was typically pretty sensitive to begin with, but it seemed to go into overdrive with the way his shirt brushed against his nipples.
He didn’t get it. What was this quirk? He didn’t usually wear a binder because he was flat chested enough that it didn’t make him dysphoric, but they began to swell as the need for…something grew stronger.
“Midoriya, stay for a minute.”
Izuku looked up, not realizing his classmates were already packing up and leaving for the day. Man…he was really out of it, wasn’t he?
“Yes, Aizawa-sensei,” he muttered.
Aizawa eyed him curiously and raised a brow. “What’s wrong with you?”
Izuku squeaked. “W-what? Um, it’s nothing, sir.”
Aizawa sighed. “You’ve been distracted and shifting in your seat all day. You’re not usually that restless. Are you hurt?”
Izuku flushed red, his cheeks burning. “No, I uh-” he shifted nervously. “I was hit by a quirk last night.”
Aizawa looked entirely unimpressed, but not one bit surprised. “A quirk.” He deadpanned.
Izuku smiled sheepishly. “She said it wasn’t dangerous! It’ll wear off in a week, I’m fine sensei, really!”
“What effects are you under?”
Izuku blushed hard and looked away. “I-it makes my chest really s-sensitive,” he stuttered. “B-bigger, too, I think.”
Aizawa frowned. “And it’s been getting worse?” he deduced. “You weren’t as distracted this morning.”
Izuku shifted, wanting to shield himself by crossing his arm, but it only served to put more pressure on his breast.
He whined, the sound leaving his lips without his consent. “Sensei, it hurts.”
He was too distracted to notice how Aizawa’s gaze shifted, going from concern to hunger. “Can you show me kid?” he asked, voice steady. “We might need to see Recovery Girl.”
Izuku nodded shyly. Aizawa checked that the classroom door was locked as Izuku began unbuttoning his school uniform. His fingers were trembling, heat spreading through his body as he revealed his breasts.
They were still small, but he could no longer be considered flat chested at this rate. They were plump and firm, his hard nipples a deep red. Izuku looked away as Aizawa eyes lingered on his chest.
“Can I?” Aizawa asked.
“S-sure.”
Izuku moaned. A large hand cupped his tit, gentle but firm. It sent pleasure shooting straight to his clit. Izuku knew his cheeks must be beet red, what was he doing moaning in front of Aizawa-sensei? God, how could he ever look the man in the eye again?
“S-sorry sensei, I-”
Aizawa kept his hand firm, rubbing his thumb against the sensitive flesh. “It’s fine kid, it’s just the quirk.”
Izuku bit his lip and nodded, but still couldn’t meet his eyes. Aizawa-sensei was attractive, and he’d been the subject of far too many sleepless nights spent rutting against his pillow for this kind of attention not to reduce Izuku into a horny mess.
Aizawa kept a steady pressure on his breast, his intense focus never wavering from Izuku. He removed his hand, and before Izuku could mourn the less, he pinched Izuku’s nipple.
“Ah! Sensei-”
He rolled the pink bud between two calloused fingers, and pulled. Izuku suddenly wondered if the man could make him cum from touching his nipples alone.
Aizawa hummed, swiping his thumb over the bud, and bringing it to his lips. “You’re lactating.”
Izuku’s eyes widened. “W-What?”
He continued pulling on his nipple, coaxing the milk from his breast. “The quirk, it’s making you lactate.”
Izuku buried his face in his hands, wondering whether it was possible to die from embarrassment. Aizawa frowned, working his nipple harder as he messaged the tender flesh around it.
“I think you’ll feel better if we milk you dry,” Aizawa said casually, as though this experience wouldn’t fuel his masturbation fantasies for the next five years. “The flow has stopped but your tits are still full. I don’t think we’ll get the rest out without some added suction. Can I try something?”
Izuku nodded, somehow horny and humiliated in equal measure.
He squeaked as Aizawa pulled him into his lap, his legs straddling his teacher’s thighs. It left his breasts at the perfect height for Aizawa to latch onto him and suck.
“Ah!” he ground his pussy into his teacher’s lap subconsciously, his milk filling Aizawa’s mouth. “Sensei it-” he panted, “that feels good-”
Aizawa growled, sucking his nipple hard. He had one hand cupped around his other tit, kneading it firmly, while the other was wrapped around Izuku’s waist and pushing him down onto his lap. The throbbing need in his pussy was overwhelming, and sensei’s hardening cock pressed up so perfectly for Izuku to rut against it mindlessly.
He felt so close, but it wasn’t enough. The white-hot sensation of sensei sucking him dry combined with the hard cock now rutting back against him was making him lose his mind. Touching himself had never come close, and this should be enough to make him cum, but he was so-
“Empty,” he gasped, a desperate plea as tears of frustration welled in his eyes.
Aizawa was all too happy to oblige. His hands fumbled around Izuku’s pants, shoving them down to his knees to reveal his pussy, already drenched in slick. Aizawa refused to pull away from his breasts for even a moment as he pulled out his cock, hard and thick, from the confines of his hero costume.
Izuku whimpered at the loss of stimulation for the few moments he was unable to rut mindlessly against Aizawa’s cock, only to be slammed onto it in one swift motion.
Izuku cried out as his cunt was so suddenly stuffed, his sensei’s cock filling him up so perfectly. Aizawa thrusted into him desperately, setting a brutal pace as his tits and pussy were assaulted relentlessly.
“Fuck,” Aizawa growled, “So fucking perfect, ah-” He groped Izuku’s tits hard as his cock tried bullying past his cervix. “Love your milk, baby- tastes so fucking good.”
Izuku whimpered, tears streaming down his cheeks as pleasure overwhelmed him. He just needed a bit more, he was so close-
“Gonna return the favour,” he grunted. “Fill you with my milk, shit!”
“Yes yes please, sensei-” he babbled incoherently as Aizawa’s hips began to stutter.
“Fuck, I’m gonna fill you with my cum, baby” Aizawa rasped in his ear. His fingers were gripped around his hips tightly enough to leave bruises on his skin. He panted as continued muttering about filling Izuku, “shit,” he hissed, feeling Izuku tighten around his cock. “You want that? You want me to stuff you with my seed and breed you? Fuck my cum so deep inside that you get pregnant?”
Izuku nodded, sobbing on Aizawa’s cock.
“Fuck, kid-” he thrusted up, hard. “Gonna keep these titties full, shit- so I can suck them dry whenever I want,” Izuku moaned.
“Cum, baby,”
The words pushed him over the edge. His pussy clamped around his length as his body seized from the force of his orgasm. Aizawa fucked him through it, groaning loud and deep as he emptied himself inside of Izuku, his seed painting his insides white.
It seemed to go on endlessly, electricity coursing through every nerve making his toes curl and body go rigid. Aizawa cock continued pulsing more and more cum inside of him, causing his stomach to swell with how much hot virile semen filled his hole.
When he finally came down from his orgasm, he slumped against Aizawa’s chest, the aftershocks making Izuku’s walls throb against his teacher’s softening length.
He didn’t have it in him to feel ashamed, not when Aizawa had lost just as much control. He steadied himself, breathing hard as Aizawa held him.
“Can we chalk that up to another effect of the quirk?” Izuku asked, aware of just how much trouble Aizawa could get in for fucking a student.
Aizawa huffed out a laugh. “Sure kid.”
Izuku rocked his hips, feeling his sensei’s spent cock twitch inside of him, and hummed. “Quirk won’t wear off for another week, sensei,” he sighed happily.
“I suppose I’ll have to help you out again, won’t I?”
Izuku smiled against his teacher’s neck. “Guess so,” he agreed.