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Something strange was going on with your twin brother.
You don’t know exactly why it was happening, but you believe it started around the time that you first mentioned going on a date.
Shouto had stiffened up instantly, staring at you with such an intense expression that you almost took a step back. “A date?” His voice was quiet, but you could sense the underlying threat behind the words. It scares you a bit, a feeling that you weren’t used to from your twin.
“Um, yeah,” you say hesitantly, “a date. I think it’s about time for me to start getting out of the house. You guys are all grown now, and I don’t need to worry so much anymore.” A darker, more secret reason whispers in the back of your head, telling you that the relationship you and your twin have isn’t healthy. Insisting that if you don’t free yourself now, then you never will.
“But I - we still need you.”
“I know,” you give him a smile as you finally realize exactly what he’s worried about. He’s afraid you’ll disappear just like Touya. Just like your mother. “And I’m not going anywhere, I promise! I just need to start having my own life.” You reach up to ruffle his hair like you’ve done since you were kids, only for him to pull away after a second.
His expression darkens as he turns on his heel and walks away without a single word, leaving you standing in confusion as to what just happened. You glance over at your brother Natsuo, only to see a look of concern on his face that he quickly hides as he notices you watching him.
“What the hell was that about?” You ask him, only for him to be unable to meet your eyes.
“I don’t know,” he says quickly, “but I gotta go.” And then he too walks away from you without saying a word, leaving you even more confused than you were before.
You glance at the time, realizing very quickly that you need to start getting ready for your date. You hurry to your room, jumping into the shower and turning the water as hot as you can stand it. Despite being twins, you had inherited more of your mother’s quirk than Shouto who was more balanced between the two, and it left you feeling cold much of the time.
When you were kids, Shouto would cuddle up with you, pressing you against him as he warmed you up with his body. He didn’t even need to activate his quirk as that side of his body was naturally warmer. You would snuggle close to him, burying your face into his side until your shivering subsided.
You’re pulled from your thoughts by a strange shadow, and you feel a sense of unease go through you as you poke your head out. “Hello? Is anybody there?” But the heat of the water has caused steam to spread out through the entire bathroom, and you’re not able to see anything. Nobody calls back out to you either, so you simply shrug and chalk it up to your imagination.
You finally step out of the shower, body feeling more warm than it was before as you wrap yourself up into a towel. You dry yourself off, choosing a pretty but not over the top dress to change into before you move to the mirror to begin to put makeup on. You glance at the time again, realizing that you’re going to need to be quick about things if you don’t want to be late.
And that’s when your twin brother storms into the bathroom. You jump a bit at the suddenness of it, as he hadn’t even called out that he was coming in. You’re not embarrassed, as you had seen each other naked before, being twins who were downright determined not to be separated.
But this seems different, the air snapping with tension as Shouto’s eyes wander over your body still glistening with moisture from the shower. “Is that what you’re intending to wear, dear sister?” His voice comes out brittle, mocking, and you’re taken aback at it.
“I - I mean, yes,” you say timidly, “I think it looks nice, don’t you?”
But instead of complimenting you, his eyes go even darker as he stalks towards you. You take one step backwards, followed by another, and another, until your back hits the wall of your bedroom and you can go no further.
His body traps you against the wall, one hand coming to rest above your head as he leans in close to you, hot breath fanning against your face. You have never seen him like this, and you find yourself trembling a bit. “You look too nice,” he growls a bit, “and I don’t think you should be going out like that.”
“Shouto, what the hell are you talking about? You’re acting so weird!”
Am I?” He lets out a dark chuckle. “Because personally, I think I needed to act like this for a while.”
“Let me go. You’re going to make me late.” It’s a sharp command as you push yourself away from the wall, fully expecting him to finally drop this insanity and let you go. Instead he pushes his body against you, forcing you back to the wall and pinning you with his hips.
“Late?” He repeats your word as his lips curl up into a smirk. “I guess I need to keep you here for a little longer then.”
“You - want me to be late? Why?”
“Because you’re not going on this date.” It isn’t a question, or a request, but a cold statement of fact. He’s simply determined that this is what’s happening, and he won’t change his mind on it.
“Shouto, I already told you that this doesn’t mean I’m going anywhere,” you try to comfort him, calm him down from this madness. “It’s just a date.”
“No, you’re right that you’re not going anywhere. You’re mine, sister.” And with that, he wraps his hand around the back of your head, pulling you into a forceful kiss. Your sudden gasp of surprise allows his tongue to invade your mouth, massaging against yours as his teeth graze your lower lip. He pushes your legs apart, knee coming up to grind against your core through the thin barrier of your panties. You try to pull away, but he merely tightens his grip on you and pulls you closer, as if he’s attempting to meld the two of you together so that you can never be apart.
He finally pulls away from your mouth, leaving you able to pant for breath as you stare at him in a new light. His lips begin to trail down your neck, sucking and licking at your heated skin. You can’t stop the small moan of pleasure that leaves your throat, and you feel rather than see his lips curl into a smirk against the skin of your neck.
“What the - Shouto, this is - “ Your words are a jumble, brain not able to keep up with the events that are happening.
“Wrong?” He finishes your sentence for you, as the two of you have been able to do for years. “Well, I don’t agree. Who can ever understand you as well as I can, sister? Who is the one who’s been taking care of you all this time?”
“That doesn’t mean - “ You waver a bit, shame clouding your senses as you find yourself secretly agreeing with his words. You shake your head as you try to push the thoughts from your mind. “We can’t do this.” You make your tone as firm as it can be so he realizes this isn’t acceptable. “We’re going to pretend this never happened, Shouto, and it’s not going to be mentioned again.”
You push away from the wall again, but this time he lets you, moving to the side so that you can walk away. You glance at his face, but his expression has shifted to one of complete neutrality, revealing nothing of his thoughts. An ominous thought crosses your mind that he really isn’t going to let this go, that he’s just biding his time. But you shake it from your mind as you rush out of the room in hopes of salvaging your date, ignoring the throbbing ache between your legs and the voice in the back of your head screaming that you shouldn’t be running.
✧༝┉┉┉┉┉˚*❋ ❋ ❋*˚┉┉┉┉┉༝✧
Unfortunately, there’s no salvaging the date. By the time you’re able to get to your phone to text that you’re running late, you already have an angry message telling you that it’s cancelled and not to contact them again. You give a sigh at the lost opportunity, wanting to curse your brother for causing you to miss it. But despite the fact that they really seemed like a nice person, you feel more relief than disappointment.
That’s when you see Natsuo glancing at you with a look of contemplation. You try to meet his eyes, but he instantly looks away from you. “What it is, Natsuo?”
“Late for your date, huh? You were looking forward to it too.”
“I - yeah I was, but I decided not to go.” You realize how weak of a lie it is, as you’re still wearing the dress you intended to go out in. But Natsuo takes you at face value, even though he has to know it’s not the truth. He hesitates for a second before he leaves, finally turning to you and pointing at his own neck. “You may want to hide that.” And with those words, he turns to walk away.
You rush to a mirror to see what he’s referring to, only for your heart to sink into your chest at what you see. A hickey is clearly visible on the column of your neck, right at your pulse point. And there’s only one person who could have made it.
You head quickly back to your room, locking the door as your mind spins with ideas, trying to find a way to deal with this situation without encouraging your twin even more. Unless you want to encourage your twin even more, your traitorous brain whispers to you.
But you come up with nothing, and you finally give up, resolving to think more on it when you wake up. You crawl into bed, laying your head down and instantly drifting into a heavy sleep.
✧༝┉┉┉┉┉˚*❋ ❋ ❋*˚┉┉┉┉┉༝✧
You wake up slowly, fog trying to lift from your head as you struggle to realize what’s happening. You feel a heavy presence over you, warm and comforting even though you can’t see who it is.
But you suppose it doesn’t really matter that you can’t see who it is, because you know immediately.
Your twin brother is straddling your body, one hand running down your sides and one hand under your shirt, tracing your skin with a hot finger.
Your eyes suddenly fly open, only to see Shouto’s face inches from you. “You’re finally awake,” he murmurs at you as if there’s nothing wrong with this situation, nothing wrong with him straddling his twin sister as she sleeps. “Just another reason you need to be protected, sister. You didn’t even realize there was anything wrong.”
His cold hand slides under your pajama pants, pressing firmly against your lower stomach and causing you to shiver a bit. “Shouto,” you whimper a bit, “why are you doing this?”
“Because you’re mine,” he says without hesitation. “You’ve been mine the second we were born. Mine to protect and take care of.”
“Protecting and taking care of me doesn’t mean - doesn’t mean this!” Your voice becomes stronger, only to end in a gasp as he cups you between your legs, fingers trailing along your panties.
“Then why are you wet?” He whispers at you, fingers dipping below the waistband of your panties and sliding along your slit. He pulls his hand out to show the evidence of your arousal, and you feel heat rush to your face. “Your body knows it belongs to me. Your mind just needs to be convinced of it.”
And with that he pulls your shirt above your head before you can react, mouth quickly latching over a nipple and suckling. You let out a whimper as his cold fingers tweak the other nipple, rolling it in between as it quickly hardens under his touch. His other hand isn’t idle as he traces patterns up and down your skin. Your sides, your thighs, down your chest, heating your skin up and making you feel like you’re on fire.
“Shouto,” you whimper, and his face twists into one of pleasure at hearing his name falling from your lips like a soft prayer.
Two fingers press against your throbbing clit as he continues to suck your nipple, letting one fall from his lips with a pop as he switches to the other one. He begins to rub tight circles on your throbbing clit, causing you to tremble from both desire and shame.
“This is wrong,” you whisper to him, almost trying to convince yourself more than you are him. “We shouldn’t be doing this, it’s so wrong - “
He lifts off of your nipple as his stare bores into you. “And why is that? What’s so wrong with this? I love you, sister, and you love me. You’re my other half.” His voice trembles a bit, and your heart breaks just a little.
Before you’re able to think of an argument against this, he presses down on your clit harder and you let out a moan. He begins to slide down your body until he’s settled in between your thighs, gently removing your pants and panties. He wastes no time burying his face into you, licking along your slit and tasting the juices of his beloved twin sister.
He groans into your flesh, lifting up long enough to say something. “You taste so damned good.” He dives back down, spreading your folds apart as he reveals your aching clit to his sight. He gives a soft kitten lick along the bead before losing control, sucking your clit into his mouth with a loud pop as his tongue lashes against you.
You’re not able to hold back your moans now, bucking your hips up towards his mouth as he works your clit like he’s known your body for ages. And really, isn’t that the truth? He wasn’t lying when he said he was your other half, and you’ve always felt the same way. Isn’t this the way it’s supposed to be?
He must notice your change of resolve, as you can feel his lips curve a bit against your flesh. He slips two fingers into your dripping heat, and you have to bite into your hand to keep your shout from leaving your throat. He stops what he’s doing long enough to rip your hand away from your mouth. “I want to hear your noises, sister. Don’t hold back.”
“But the rest of the - “
“Fuck the rest of the family,” he snarls a bit, “they can never understand the bond we have together.”
And then he’s scissoring his fingers inside, and any words you would have responded with are gone. The sting of him stretching you open feels amazing, and you thrust your hips down to meet his fingers as he slips a third in. Your pussy is dripping by this point, and so the stretch barely even hurts, and you whimper as he grazes a sensitive spot against your walls. He chuckles a bit as he removes his fingers abruptly, pulling away from you and causing a whine from the back of your throat.
“Oh, I’m not done with you yet, sister,” he murmurs as he removes his pants, revealing a lack of underwear and his cock standing at attention. He’s thicker than you expected, with a long vein running down his length that twitches as you watch. There’s a curve to his cock, and his cockhead is an angry red from arousal, drops of precum already leaking out to trail down onto his heavy balls.
You find yourself unable to stop yourself from licking your lips at the sight, and he laughs a bit as he lines himself up with your entrance. “This is going to hurt a bit,” he whispers at you, “but I promise it will feel good soon.”
You give a quick nod as he moves, your tight inner ring of muscles burning and stinging as your flesh gives way, your twin finally taking his little sister’s virginity. You’re trembling a bit from the pain even though he moves slowly, inch by agonizing inch. He sees the pained look on your face and gently soothes you, planting open mouthed kisses along your face and brushing your forehead with his.
It distracts you a bit, and you relax enough for him to finally bottom out inside of you, your brother’s cockhead resting snugly against your cervix as your walls pulse around him. “Fuck,” he hisses out, “you feel so good, little sis. So tight and wet for your brother, such a good girl.”
At his praise, you clench down around him and he smirks a bit. “Do you like it when your brother talks about how good of a girl you are?” He whispers, voice lowering with seduction.
You don’t even have to answer him, your pussy doing the talking for you as you clench down again. “Please, I need you,” you whimper as you try to thrust your hips back against him.
He takes you at your word, gripping your hips as he begins to thrust inside of you. The veins along the underside of his cock slide deliciously over your inner walls, and you feel tension building up inside of you. He pins your arms down above your head with one strong hand as he pounds inside of your soaked pussy, his fingers still gliding along your aching bead. The wet noises your bodies make as they connect are positively lewd.
“Cum for me sister, cum for your big brother,” he groans into your ear as he pumps inside of you, “I want to feel you cum around my cock.”
As if on command, the tension inside of you snaps and you cum with a choked sob, eyes rolling back into your head and legs trembling as your walls flutter around Shouto’s cock. “Fuck you’re so tight, hngg, you feel so good.” His movements become downright feral, and he hoists your legs over his shoulders as he forces your knees to meet your body. He bottoms out inside of you with every single movement, cock battering against your cervix as if he’s trying to force his way even deeper inside of you.
“Fuck, going to cum, shit - going to cum deep inside of your cunt,” he grunts out, “would you like that? Do you want me to breed you, sister?”
You’re too far gone to think of anything but wanting to feel your brother cum inside of you. “Yes, fuck yes, breed me, please, cum inside of me, brother!”
At those words, he loses control completely, unable to hold himself back. He slams himself all the way up your unprotected cervix as his cock twitches inside of you. Thick, hot ropes of cum shoot inside of you, filling you with warmth and pushing you over the edge again. You squeal as you cum again, even more intense than the first one. Your walls choke his cock as they pulse around him, milking his cock for every drop of cum he has.
Although his cock is oversensitive, he forces himself to remain inside of you, collapsing against your chest as he pants. You wrap your arms around him, running your fingers through his hair as you try hard not to think of the implications of what just happened. You want to regret it, to feel disgusted.
But you don’t. Lying here with your twin brother’s cock buried inside of you and your insides coated with his cum makes you feel more whole than you ever have. It’s like an emptiness inside of you has finally been filled, and you realize something.
You’ve always needed your big brother, in every single way.
“I love you, Shouto,” you murmur into his ear, and you feel his heartbeat speed up against your chest.
“You don’t - hate me for what I did?” He asks in such a childlike voice that it makes your heart ache.
“I could never hate my big brother. My other half.” He lets out a sigh of pure pleasure as he nuzzles against your neck.
“But what now?” You ask quietly, thinking of the rest of the family finding out about this. “What if they find out?”
Shouto gives an unconcerned shrug. “Pretty sure they’ve already guessed, at least about how I feel about you.”
This news should come as a complete shock, but you remember Natsuo’s behavior recently and realize that he must have known what was going on. He just looked the other way.
“And our dear old dad?” You say in a bitter tone. You never got half the treatment that Shouto did from him, but it doesn’t matter. Anything done to one of you is like it’s being done to the other. You’ve always had a sense of each other’s pain, a deep bond running between you.
“He won’t stop us,” Shouto says hesitantly, as if afraid to speak the words.
“What makes you say that?”
“His prized possession getting his sister pregnant, keeping his pathetic bloodline pure and possibly giving him strong grandchildren? Trust me, he won’t stop us.”
A sense of panic rises up in you at the thought of your father ever getting his hands on any children of yours, but Shouto is quick to shush you.
“I would never let anything like that happen to you,” he murmurs to you, “or our children.”
“Should we even have any?”
“We can decide later,” Shouto shrugs again. “But just know one thing. No more talk of dating. You’re mine, and mine alone, and I am never letting you go no matter what. Do you understand?”
“Yes, I understand,” you find yourself saying with a smile. “After all - “
“You’re my other half,” you both say in unison as Shouto begins to move inside of you once again.