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Katsuki kicked at the floor-to-ceiling viewscreen from his seat for what had to be the eight thousandth time. She had long ago stopped looking up from her reading but it was certainly distracting when she was in the middle of one of those scenes.
He growled and Ochako tried very hard not to associate the sound with how the werewolves she was reading about growled at their heroine because she wasn’t supposed to have those thoughts about her brother. Definitely not. That was wayyyyy forbidden territory. But—
She snuck a glance at him. Nobody would argue that her brother was devastatingly hot. Yoked shoulders, thick arms roped with muscle, his chest of wide pectorals and the definition of his eight-pack clearly visible in his standard issue long-sleeved thermal. Constantly messy blond hair, crimson eyes—a result of genetic manipulation in previous generations—and a mean smirk that exposed sharp, gleaming white teeth.
And when they were both standing he towered over her.
If he were anyone other than her brother, her fantasies would have run wild with thoughts of him. As it was, she had a fairly tight rein on those thoughts. The occasional morning when she woke up with her hand in her panties and soaked with need, thinking of his derogatory sneers, didn’t count. Stupid REM sleep. Probably the lingering effects of her time in the cryo chambers.
Ochako was definitely not into her brother like that.
They didn’t exactly look like siblings. She clearly took after their dad, he after their mom, and he’d never been the protective older brother type. So it wasn’t her fault that she sometimes might not think of him as family. Especially since they’d barely met for the first time in seventeen years before the juggernaut of a space station took off with its 67,000 occupants as they migrated to a new planet. She’d been living with her childless aunt and uncle half a world away in order for her family to avoid penalties for violating the one-child per household mandate.
“Fuc-king bo-o-ored.” Each extended syllable was punctuated by another kick.
She released an annoyed huff, which was a mistake.
“You got something to say, Round Face?”
Ah, yes. His pleasant nickname for her. So she was a little chubby, so what. It would be something if his delivery was even mildly affectionate but instead it was clearly—purposefully—antagonistic.
Rise above it , she reminded herself.
“You accomplish, let me see…” She tapped a finger against her chin. “Oh, right! Exactly nothing by sitting there and bitching.”
There went his sneer. Those mesmerizing almost-fangs of his. “Yeah? And I suppose you have a better idea?”
Ochako waved vaguely. “The grav-training room, the gym, VR sparring with someone in another pod.”
Under normal circumstances, would have had access to the entire station but there’d been some sort of concerning viral outbreak and so all pod units were to quarantine until further notice. That had been seven months ago. Every time the station tried opening up a section of pods the virus struck again and quarantine went back into effect.
Their parents, aunt, and uncle had chosen to tuck back into intermittent cryo but neither Katsuki nor Ochako wanted back in the tubes just yet.
“You think I didn’t do that already for the better part of three hours this morning?”
She knew he had, admittedly. It was what he did every day. But he usually went back for subsequent rounds while she stuck with her once daily body weight training and yoga and the desire to read through as many books in her to-be-read list as possible.
“Ever try picking up something with words?” Ochako waved her tablet at him.
“Look here, Round Face. The type of energy I want to burn right off now has nothing to do with squats or push ups or lifting weights…” The man who was older than her by only 9 months paused and then chuckled darkly. “Well, maybe they do. But I’m not gonna find that in a book.”
Ochako blushed. She may not have much practical knowledge—all she’d done was share an incredibly one-sided kiss with Izuku after he’d confessed to her before quarantine—but, well, she knew enough based on her erotic books. She understood the mechanics, at least.
“You’d be surprised,” she murmured.
He grunted. “That so?” His chair swiveled and Ochako gulped as a wicked glint entered those feral red eyes of his. “You watching porn over there, baby sister?”
“ No !” she cried, perhaps a little too quickly.
“Ah. Reading porn, then. You little pervert.” His big body stood, unfurling from the seat to cross the room and loom over her. Even with her rounded hips and belly and her large breasts that sometimes made her feel like the biggest girl on the station, he made her feel small.
Ochako pressed deeper into the couch cushions behind her. “W-What are you doing?”
Lightning fast, he snatched her tablet from her hands and when she would have lunged for it, planted his knee between her legs right up against her center and set his free hand wide to encircle the base of her neck. She scrabbled at his forearm but his reach was too long and when she tried to shift up and away from his knee it only made her rub her already aroused pussy against him.
His eyes watched her for a moment as she fought before sliding to the tablet screen that she hadn’t had time to lock. His eyebrows lifted but he didn’t say anything or show any other reactions as he read the page.
Eventually, Ochako just settled for wrapping her hands tightly around his forearm, reminding him that she may not be fighting but that she was biding her time. When at last his eyes slid back to her, his gaze swept her from head to toe consideringly.
“You’ve been holding out on me.”
She choked as the thumb around her neck eased up to rub a slow path up and down. “I have not!”
He tossed the tablet to the far end of the couch and leaned down into her space until her head was tilted back over the top of the cushions and she’d released his forearm to shove at this chest. When he shifted his knee, pressing a little closer, she couldn’t help how her eyelashes fluttered.
“Never knew I had such a filthy-minded little sister. It’s fucking hot.” He nosed behind one ear, breath hot as those sharp teeth grazed the curve of her ear. “You wet for me?”
She shook her head. “Not for you.”
He hummed. “But you are wet. Good to know.” His free hand dropped to her rounded hip and tugged her forward before shifting his knee up and down into her center.
She clenched her eyes shut, wheezing, “Why are you doing this? It’s wrong. We can’t .”
“We can ,” he countered. “I’ve been beating off to that ass of yours for months and I’m so horny I’d fuck the wall if there was a hole.”
Her eyes opened at that and she sank her nails into his chest, making him wince. “Really? Your sister is a decent alternative to a hole in the wall?”
“Stupid.” He kept forcing her pussy to ride his knee. “Fucking the wall seemed like the only option to keep from fucking you when my hand wasn’t enough anymore.”
Her mouth dropped open and he licked into the open space, sealing his mouth against hers. She should have ripped herself away from the kiss but a needy whine escaped her instead and he took that as a sign to shove his tongue deeper, as though mapping one wet hole to prepare for navigating the other.
Katsuki groaned into her mouth. “Fucking knew my baby sister would taste this good.”
She shoved at him again. “We can’t , Katsuki. You’re my brother—”
With a quick motion, he twisted her body so that she was laying down and threw the cushions along the back of the couch to the floor before shoving his body between her spread thighs.
He began to rock his hips into the space where his knee had been, forearms on either side of her head. “Not like I can breed you. Our DNA was crafted in a lab just like our parents and grandparents were. Bits and pieces of good qualities from all over. Perfect humans incubated in tubes.” He rocked harder and she hissed air between her teeth, her hands grasping at his shirt to pull him closer. “Some of those base pairs may be the same but that’s it. And our DNA is already on file to make our own little test tube babies some day. We’re infertile. What’s to stop us from satisfying some—” He halted to swivel his hips and she felt the ridge of his cock pressing into the seam of her standard issue trousers. “—biological urges?”
“ Katsuki .” Perhaps she’d meant to sound chastising but instead his name came out reedy, wanting.
Her brother slid a hand up under her thermal shirt to grasp a handful of her bra-covered breast as he continued to hump her. “That’s it. Let your big brother give you what you need. I’mma fill this pussy up with so much cum you’ll be dripping for days.”
She cried out when he yanked the cup of her bra down to pluck at the raised flesh of her nipple. “You have a filthy mouth.” Her reproach meant nothing as she lifted her legs to wrap them around his waist.
His mouth was at her ear again. “As soon as I get my lips and tongue on that juicy cunt, you’ll see just how dirty it can be.”
He pulled back and she missed his weight, his warmth, but he was yanking her stabilizing belt free—the one that would ground them to the floor if the station lost gravity—and then her pants and underwear down and off. As he removed her underwear, a string of slick followed the fabric until it got thin enough to release and drip over the couch.
“Like fucking Christmas,” he growled. He grabbed the backs of her knees and pushed, pushed, pushed until only her shoulders and upper back remained on the couch beneath her, the rest of her body lifted up into the air, her knees slung over his shoulders.
Katsuki didn’t announce himself. He just wrapped his arms around her legs, pulled her pussy lips open to either side and dove in, tongue digging deep into her sopping wet cunt.
Her cum made his cheeks and nose shine as he rubbed his face all over her, his sloppy licking filling the air with sound that made her breathing come harder. His tongue was long and he slithered it into her, opening his eyes from his feast to stare down her inverted body into her eyes. She felt how his jaw worked against her and squealed when he released one side of her lips to circle two firm fingers around her clit.
She shouldn’t have been able to move but she bucked against the sensation, crying out, and watching her brother’s eyes grow completely dark, the red of his eyes completely eclipsed by blown pupils. He wouldn’t let her look away as he ate her, tongue-fucking her and steadily increasing the pressure on her clit until she couldn’t keep her eyes open anymore.
So much of her body’s own cum dropped out of her, slipping between the cheeks of her ass and slowly dribbling down the line of her spine. Katsuki made rapturous sounds, face burrowing as far between her folds as he could with the messy sounds of her wetness competing with his hungry snarls.
It was the vibration of his rumbling noises against her that tipped her over the edge, her release drenching his face further as her body bucked against his hold. He kept going and going until she was crying and begging him to stop. She squinted through her lashes wet with tears to watch him shake his head and dive in again, forcing howls from her throat as her cunt pulsated around a tongue that was no longer enough.
When Katsuki finally released her, he shuffled back just enough to let her sore body lay flat again before he went to yank his own clothes off. The shirt landed on the floor and he had his pants unsnapped and unzipped when his eyes zeroed in on how she continued to drip between her thighs, still spasming from the forced orgasms.
He yanked his cock from his pants, not bothering to finish removing the garment, and crawled between her spread legs as she made room for him.
His hand curled around her neck, not to squeeze but to hold and force her gaze to his. He ran the head of his dick through her overflowing juices. “You’re gonna give this to your big brother any time he wants, aren’t you? Let me fuck you all over this stupid pod and pump you full. Aren’t you?”
The slow glide of his head up and down her slit, pausing to fuck against her clit, made her head spin. “Yes, but Kats—”
“No buts.” He dropped his gaze as he lined himself up, clearly mesmerized by the sight of her. “You were tight on my tongue. I can’t wait to feel this creamy little cunt cinching around my cock.”
“But Kats—”
He leaned over, smearing her own juices all over her face as he kissed her, licking her flavor onto her tongue as he pressed into her. She whimpered into his mouth and he cursed, shoving and shoving, forcing the fit until he was planted.
“God damn , you’re so tight,” he rasped, pulling back again to watch himself fuck her. He paused and she hiccupped in embarrassment when he paused to dip a finger down. When he brought it back up, it was smeared with blood. “This what I think it means or am I fucking you on your period?” He pulled out a little and shoved back in, his eyes closing against the sensation. “Not that I’m stopping either way, but I want to adjust my kink brain to the right frequency.”
“I tried to tell you—”
Katsuki leaned forward, shoving himself in and hitting a spot at the end of her pussy that made her screech. “First or period?” He punctuated his question by snapping his hips back and ramming into her, then stirring himself up in her.
“First!” she gasped, reaching down to scrape her nails over his pants-covered legs.
“Shit, I must’ve been a really good boy in my past life,” he crowed, snapping out and in again. His hands wrapped around her calves on either side of him until her legs were vertical against his chest, her legs chubby enough that the insides of her thighs touched. “How is it possible for you get even tighter on me? Fucking Christ , I can feel you pulsing around me.”
She was. It felt so good, too good.
He was big and the stretch had been uncomfortable but it was like her body had immediately adapted to accommodate his size. “Big, big brother,” she cooed.
“Little— nnnngh —little sister. Can’t believe I got to pop this juicy little cherry.” He fucked her harder, her breasts jiggling unevenly as one bounced more from being freed from her bra. “Gonna nut you so good.”
Her sigh turned into a whine when he dropped a hand and wedged his thumb between the seam of her pussy lips to roughly rub her clit off. “Good little brother-fucker. Fuck, almost wish I could knock you up, see those tits dripping milk so I could suck on them.”
“ Katsuki .” It was dirty, too dirty, but she couldn’t help how his words edged her that much closer to coming again.
“Fuck, fuck, fuck .” He rubbed her clit harder, cranked the speed of his hips faster as he rammed into her. “Like that, do you? Like the thought of your big brother breeding your little cunt?”
She scraped at his knees, her back bowing. “‘m your good little sister,” she moaned. “Do whatever m’big brother sayssss ,” she hissed. “Oh, don’t stop. Please don’t stop.”
Katsuki leaned over her, pressing her straightened legs in toward her body. “Look at me.” His hips shoved deep and stirred, the squelching of the movement so unbelievably pornographic. “ Look at me .” She forced her eyes open and the red of his eyes was back, blazing hot. “I will never stop. You’re mine for-fucking-ever. Got that?”
He pulled out until the tip of his cock sat just outside the entrance of her pussy. Tears trailed down her face into her hairline. “Yes,” she sobbed, reaching up to curve her hands along his jawline. “ Always .”
She thought flames may actually ignite in his eyes but he turned his face to bite the inside of one of her wrists and then plunged inside of her with so much force that her teeth knocked together.
Ochako screamed as she came around him, her insides pulsing around his girth in waves that made him feel too big all over. Like her pussy was trying to force him out from there not being enough room. It only made Katsuki howl.
“My pussy. This is my fucking pussy— yeah , fucking shit —gonna cum, gonna fill you up, baby sister…”
Heat bathed her insides and she felt his cock jerking inside her, filling her with so much that it poured out around their connection, soaking the couch beneath her ass even more than she already had with her own juices. He kept thrusting, groaning, letting words of filth spill out of his mouth without a filter until he finally stopped, pressed as deeply inside her as he could be. The pulse of him as he continued to seed her insides made her eyes roll back in her head, delirious with the sensation.
Katsuki gave a shuddering breath and let her legs down slowly, more carefully than she’d expected. He stayed inside, body shivering until he shrank enough for her body to actually push him out. Then his blissed out eyes sought hers while his fingers scooped cum out of her. Her pussy clamped down on his fingers and he chuckled darkly.
Then he lifted his dripping fingers, trailing a line of their combined mess up her body, over her chin, before pressing them between her lips. He didn’t go deep, just enough to leave a globule there on her tongue before repeating the process, this time sucking it into his own mouth.
Then he leaned over and kissed her, swirling their cum around between their tongues.
Lips covered in their own slick, her big brother pulled away to press his forehead to hers.
“You’re mine .”
She shut her eyes, knowing it was wrong—so wrong—and not caring. “And you’re mine.”