Thread by @murcielagoAO3

#miyacest #nsfw fraternal #twincest brainrot 💖
cw: oral sex, piv sex, underage (middle to hs miyas), she/he pronouns so you can imagine whoever you want ✨

(god, fraternal miyacest is just so good??? like you get all the goodness of twincest but then also size difference??)

girls mature faster so she's taller by 5th grade and fills out first, by 7th grade her boobs are envied by all the other girls along with her curving hips and strong legs from volleyball. he's still not much to look at yet, all gangly, but he sure likes what he sees, and she

thrives on the pleading, pining looks he sends her way day and night. she turns him into her pussy hound, gets him under her skirts licking her wet slit whenever she wants because he's thrilled just getting glimpses of her bra, so of course he's going to do anything she wants.

he's short and pathetic but learns pretty quick how to pluck her strings just the right way until she's comes undone and hasn't even had to give a single order. she knows he gets hard from licking and fingering her, humps against the mattress throughout his service, but she's not

that interested in his equipment. if he's happy coming in his pants? fine by her. she wouldn't dream of letting him put it in, but once in a while she'll deign to let him suck her tits and hump her thigh, and that seems to be enough for him. she just lies there and watches him

shake through his orgasm, face scrunched and panting, and then kicks him out when he's done so she can freshen up. he's not allowed this privilege every day though, she's careful not to set that expectation. makes sure she's always the one in control and setting the terms.

couple of summers go by and in 9th grade she vaguely notices that they're the same height, but then he shoots up like a sapling and one day when they're juniors she's at school and sees him come around the

corner and is taken aback--since when did he get so tall and broad like that through the shoulders? the hand holding his books for his next class is just practically a bear paw and the shock of it all makes her so wet she has to go straight to the restroom.

she meets him after their volleyball practices to walk home together and now she sees how athletic and muscled he's gotten and for the first time she's wondering about his dick--which she hasn't paid much attention to before but now she's /thinking/ about it. a lot. /constantly./

after dinner she drags him right upstairs to do "homework" and gets his tongue between her legs as fast as possible because she can't think anymore she's so bothered and twitchy she's just got to /get off/ so she can clear her head. but it doesn't work because now she's noticing

how thick his fingers are, how deep inside her they can reach, and /god/ maybe his dick is even bigger--and if it is, how deep could the rest of him reach??

she comes all of a sudden, biting her fist and shrieking. her thighs grip his head and she bucks and bucks, her brother

groaning over her clit, sending shivers all over her skin. when her peak recedes and she's gasping and flopped on the bed, she releases her legs.

her brother chuckles, licking his lips and stretching his neck from side to side. "somethin' different today i should know about?"

/"no,"/ she scoffs, looking away, cheeks hot.

"seems like yer extra into it," he comments.

she pouts at him, squinting. "just stressed, 's all."

he lifts a brow, eyes dark when he strokes a fingertip over her clit and down her dripping puss.

the needy noise she lets out is /mortifying./

he smirks.

she whacks him with a pillow. "then hurry and do something about it, ya idjit!"

he crawls up the bed to lean beside her, hand calmly resting on her mound. "whatcha wantin' then, sis?"

"figure it out, dumbass!" she huffs, hooking an arm around his neck and pulling his head down into her cleavage.

he chuckles, nuzzling into her shirt. "yer sure in a mood."

she glares, shifting her leg to rub the front of his sweats while pulling her shirt up over her bra.

he growls, teeth tugging down the edge of lace across her tit until her nipple pops out. he licks around it once before sucking it into his mouth at the same time he curls two fingers back into her cunt.

"ahhhhhh~!" she throws her head back, instinctively rolling towards him.

brain fogged with lust, she gropes her hand inside his sweats and gasps--he's shockingly /hot/ in her hand, completely hard and throbbing and fuckfuckfuck she wants him in her mouth so /bad/. she can barely close her fingers around his girth and he moans, bucking in her grasp.

she's bending to get a look at him when he curses and tears his mouth from her nipple. he yanks her hand away from his crotch and takes deep breaths.

"dontcha worry about me," he whispers, kissing down her stomach and pinning her hands to the bed. "i gotchu."

he shoulders his way between her knees and sucks on her clit until she thrashes through three more climaxes, leaving her too weak and wrung out to try anything else that night.

then he's /gone/ for a week-long training camp and she nearly ruins her nails biting them from the constant horny, wrists sore from fingering herself and not being able to hit where he can.

she's crazy feral when he gets back, turns up the bluetooth speakers in their bedroom as

loud as their parents permit. as soon as the door's closed and locked she's pushing him into it, yanking down his tracksuit and briefs and getting on her knees.

"hold up," he captures her by the ponytail and yanks so she's looking up at him. "since when're ya wantin' dick?"

for a moment she's too embarrassed to speak, face and ears /burning./ she swallows, then bares her teeth. how /dare/ he perceive her??

"keh. just say yer not into it then, /dumbass/. not like yers is the only one around--"

his brows furrow and eyes darken in a warning she's not ready for. he grabs under her arms and yanks her up so fast her head spins. he holds her there in the air like she's a toy, the grip on her body so hard it hurts. his arms are like corded cement and for the first time ever

she feels /small/ in front of him.

his largeness steals the air in her lungs--thick neck, wide shoulders and tight abs, half-hard dick hanging between thighs she wants to bounce on so badly she's leaking.

he sets her down, hands gliding down to her waist--so tiny in his hands.

"fine," he grits out. "ya want it so bad, i'll give it to ya."

he walks her over to the foot of the bed, turns her around, and bends her over it. his hands strip down her panties before she feels his hard, hot cock slide between her thighs.

he fucks her thighs hard and fast, hand on the back of her neck. his cock slides against her pussy, which drips in anticipation of that cock slipping inside--but it doesn't. the teasing friction is /unbearable/, and she pants into the bedding, squirming.

his other hand braces on her hip, his deep voice grunting as his thrusts get more rapid. he leans his weight into it and ruts against her butt so hard it jiggles. his breaths get deeper and more urgent, and she feels his thighs quiver and then go still--he buries his dick

deep between her legs. she feels it twitching and warm liquid drips down her skin.

"hnn /fuuuuuck/," he groans, thrusting slow and shallow through his aftershocks.

his noises have her so worked up, she can't stand it any longer and whines, arching her backside against his hips.

he pulls out with a long, satisfied sigh, rubbing her back with his big hands and stepping back to tuck himself away. she rolls over and sits on the edge of the bed, his come dripping down her thighs, shaking with desire.

she spreads her knees in invitation. he smirks--something

dangerous flashing in his eyes.

"better clean up before that dries," he says. he stretches his arms over his head. "gonna take a shower, i'm /beat."/

and he waltzes out the door, leaving her /seething/.

she cleans herself up, so angry with herself for letting him have the upper hand--goddamnit! she jerks off through her anger, coming twice out of spite.

see how /he/ likes it when she's suddenly and mysteriously not in the mood--he'll come running back to her in no time.

.......or maybe not.

he leaves her alone for over /two weeks/!! she bites her lip, fuming--how could her twin do this to her?? god!! that /idiot!/

after the third week she's so upset and angry she walks home alone after school instead of waiting for him. /fuck that./ lousy asshole.

she storms upstairs after dinner and puts her earphones in while doing her homework. he follows her into their room, and her lips press thin.

she ignores him until he makes it impossible by draping himself over her desk chair, chin on the top of her head. she exhales, annoyed.

he exhales, exasperated, and take out her airpods. "hate when yer ignorin' me, sis."

"why should i care?" she huffs. "go play with yer dick

or somethin'."

"nah," he murmurs. his hands sneak under her breasts and cup them, pulling her tight to his chest. "miss ya too much, sis."

she flushes, mouth in a pout. "ha. heard ya in the shower /bro/. seems ya and yer dick are doin' just fine."

"that's different," he sighs. "an' like ya didn't get yerself off every night to torment me, eh?"

"didn't leave me a choice!" she snaps, rotating in her seat to look him in the eye. "ya got on yer high horse and rode on outta here without me, so it's all yer fault!"

"well maybe it was time i knocked ya off /yer/ high horse, huh?" he snaps back. "always orderin' me around like yer slave--maybe i liked gettin' to come first for a change."

she's so annoyed she swats his arm. "you fuck! don't make it sound like i forced ya! and don't worry--

yer off the hook forever okay? so just forget it!"

she pushes his hands away and aims to storm out of the room, so furious she could cry--but of course he grabs her before she can get away. he hoists her into his arms and she kicks her feet.

"put me down right now!"

he tosses her onto the bed and then crawls over her, caging her in. "now you shut up and /listen."/

the he gives her the shock of her life--he leans down and kisses her full on the mouth.

She's stunned, frozen beneath the heat of his mouth, the weight of him pressed against the length of her body. His lips tease hers apart and his tongue invades so fiercely all she can do is open for him and curl her tongue with his.

It's so intense she clutches at his shoulders,

arms wound around his neck and heart fluttering like a swarm of birds taking flight in all directions.

"Mmm, /god/ sis..." he murmurs between kisses that steal all her breath. "Ya drive me /crazy/..."

He rolls his hips--she widens her legs on instinct as he kisses her.

Again and again he claims her mouth. The longer their tongues entwine, and the more of his groans she swallows, the more her whole chest aches--all her weird and mixed up feelings about him, about /this/, stirring up cyclones beneath her skin.

She threads desperate fingers through his undercut and he shivers, gasping along her cheek. /"Fuck..."/

Then he whispers her name, and the way it rolls from his tongue, pleading and earnest, sacred like a prayer--sets her whole body on /fire./

She angles to capture his mouth once more but he suddenly pushes away, cursing and rolling off her. He flops on his back, an arm flung over his eyes.

"Can't do this anymore," he grits out, brows furrowed.

She sits up, hair mussed, and stares down at him, perplexed and horrified by the blade he's just struck through her beating heart.

She forms a fist and punches it down into the bed. "Bullshit! Ya can't just--just--just /kiss/ me like that an' then call it off? Fuckin' asshole!!"

"Well I can't take it anymore!" he shouts, lowering his arm and showing her the pain in his eyes. "The thought of anyone else bein' with ya makes me furious--"

"Hey!" she slugs him in the arm. "The hell're ya talkin' about /someone else/ when ya know goddamn well yer the only--"

He huffs, swatting her leg. "Ya said it before, ya fuckin' tease, sayin' ya got hordes of others willin' to be yer toy--"

"Ain't never said that!" She sits up on her knees, glaring down her nose. "The hell ya talkin' about?"

"Night I came back from camp!" he gestures angrily.

She opens her mouth, trying to think back--and the humiliation of him stopping her from blowing him and then not-fucking fucking her comes rampaging through her emotions all over again.

"Ugh!" she slugs him again, cheeks boiling. "Obviously, I was bluffin'!"

He blinks stupidly at her like some stunned and confused hoot owl. "WHAT?!"

"Don't make me say it again!" she shoves his stupid bangs in his face, ears burning.

"Well what the heck didja say that for!" he pushes the hair back out of his face and sits up on his elbows.

She sticks out her tongue and then scoffs at him, baring her teeth. "/Yer/ the one who pushed me away, remember? So what the hell am I s'posed to do, huh? An' by the way, the fuck is yer problem?! Ya don't gimme the time of day for 3 weeks and then tonight ya kiss me like that?!"

He rolls his eyes and opens his mouth a couple of times, but nothing comes out but a frustrated growl.

She groans, equally frustrated. "/WHY/ didja kiss me? Ain't never kissed me before so why now? Ya said to shut up an' listen, so hurry up an' tell me!"

"Cuz I wanted to!" he shouts, sitting up. "Wanna kiss ya real bad, all the time okay?"

Her jaw hangs open and now /her/ eyes are stupidly wide and blinking like an owl. His cheeks are as pink as she's ever seen, and he coughs, clearing his throat.

"Goddamn," he sighs, glancing away. But he reaches for her hand, clasping it tight. "Thought if I kept ya happy at home ya'd just, kinda always be mine? But it's not near enough, sis. I just--I wanna kiss ya. I want /more/, sis. Want /all/ of ya. Wanna be yers, too. S'that okay?"

She looks into his eyes, so many questions swirling in their depths, but she also sees the deep affection he's always had for her... along with the perpetual flickering flames of his serious /desire/.

"What're ya sayin'?" she asks, fidgeting. "Are ya confessin' to me, then?"

He snorts. "Guess I am."

She snorts too--it's kind of absurd, siblings confessing. But she supposes she feels the same way... wants to claim him for her own before anyone else can try and steal him away. Wants to be with him for /real,/ not just fooling around to fool around.

"Okay, bro," she smirks. "If yer willin' to give all of yerself to me, I guess I can do the same."

She rests her palms on his chest and gently pushes him to lie back on the bed, climbing over him to straddle his waist.

"I want /all/ of ya," she says, rocking her hips backward.

Those big hands of his grab onto her curves, and he hisses, muscles tense.

"That okay?" she circles her hips over his groin, which might be a little unfair of her, but she can't help herself, running hands over his clenched abs while her yearning for him pools in her belly.

"Wantcha too, sis. /All/ of ya," he nods, hands stroking up her shirt and teasing her ribs.

She gasps and arches forward, bending to brush their lips together, eager to kiss him again and feel that rush from sharing such a new, intoxicating closeness.

This time /neither/ of them holds anything back.

TBC! <333

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