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“Are you crazy? Here?” Luka’s eyes widen after hearing your proposition, his front flush with your back as he helps you with your weightlifting routine.
“Please, brother… need you so bad,” you beg him while pushing your ass back, grinding on his crotch.
“The gym is full,” he whispers through his teeth, the growing hardness between is legs betraying his attempt at self-control.
“So what?” You moan as you gradually feel your brother getting harder underneath your own sex, only separated by two layers of fabric.
“You— people will see,” Luka frowns his eyebrows, still trying to be the reasonable one as the older sibling.
“Maybe we should let them see,” you turn your head a little and whisper to him. “Maybe we can give them a show, let them watch two brother and sister fucking in public.” Your eyes are already half-lidded now.
Luka’s breath hitches, something inside him is awakening. Taking you right in front of everyone? Letting them know that yes, you’re his sister and yes, he’s fucking you?
He gulps.
Thrill is clouding his judgement and before he knows it he’s already lowering the back of your legging — just enough to expose your squelching wet pussy — and he unzips his fly and takes out his painfully erect cock.
With your back still leaning on his chest, Luka slowly slips his dick in between your moist folds, pushing it inside carefully to not make you moan too loudly — you’re a screamer, and he can’t let you draw attentions from the other gym goers.
As you feel your brother filling you up, you whimper silently, biting your lips to control yourself from making too much noise.
After several seconds, you notice that he’s not moving at all — so you try wiggling your hips slightly to signal him.
“Keep going,” Luka suddenly says. His hands are now placed on your waist, the cold of his metal arm sending shivers through your spine.
“Huh…?” You tilt your head slightly in response, already feeling stupid from having your brother stuffing your cunt full with his cock.
“Continue with the reps, or I won’t move,” he chuckles right in front of your ears, his lips grazing your earlobe.
Fucking hell, of course he’s teasing you. He is still your older brother, after all.
With great difficulty, you keep on trying to lift the weights, again and again, exerting force and flexing your muscles and complying with your brother’s demand because he just feels so fucking good.
Luka notices your efforts and he rewards you with slow motions on his parts, subtly sliding his cock in and out of your hole.
You’re trying really hard to keep on going with your reps, but the pleasure is making your head hazy and your toes curl up.
And so as your brother’s movements gradually getting quicker, your reps are getting slower — up to the point that you simply stop trying to lift the weights anymore and instead you’re now holding on to the metal bar to support yourself while Luka is giving your cunt a pounding right in the middle of the gym.
The slapping of your bodies starts making plap plap plap sounds, and you’re not sure if the two of you are even trying to hide your illicit act anymore.
The strands of his red hair are clinging to his face due to sweat, chasing rapture as his cock keeps pistoning in and out with machine-like consistency and speed.
As the coiling pleasure starts building up inside you, you can also sense your brother’s fucking is getting more erratic and uncontrollable. And then it dawns on you that he’s pounding his dick raw, he’s not wearing any condom.
“Gonna come inside you, alright? Gonna fill you up and have your tight cunt dripping from your brother’s cum right in front of everyone,” Luka whispers as he groans from the ecstasy of fucking his own sister’s pussy.
You just nod eagerly as your skin is flush with red, your release is just several more thrusts away.
“Fuck, I’m coming…! Coming inside you, dear sister!” Luka slams his hips one more time before hitting your cervix hard, reaching his peak and spurting his creamy cum inside your womb, making you roll your eyes as you too reach the climax and shudder due to the feeling of absolute bliss.
As the two of you are catching your breaths, your brother’s forehead leaning on the back of your shoulder… you finally realise just how awfully quiet your surroundings are.
When you look around, you notice that the gym is now empty, save from only the two of you there.
Luka laughs hysterically before pulling out and fixes himself, then helps you with your bottom.
“Well… guess we did give them a show,” Luka remarks with a grin, feeling awfully amused by the whole situation.