The car hummed along the empty highway at night, windows cracked just enough to let in the warm summer air. Jake gripped the wheel tight as his sister Emma shifted in the passenger seat beside him. They were both adults now, home from college for the summer, but the long drive back had already stripped away any polite bullshit.
"Fuck, I'm horny as hell," Emma said suddenly, her voice low and direct. She tugged her shorts down her thighs and kicked them off, leaving her in just a thin tank top and panties. "Been thinking about this ride all day. You?"
Jake glanced over, cock twitching in his jeans. "Yeah. Same. Pull your panties aside and show me that pussy."
Emma didn't hesitate. She hooked a finger in the crotch of her panties and yanked them to the side, spreading her legs so the dashboard lights caught the wet shine between her folds. "Look at it. Already dripping. Bet you'd love to fuck your sister right here."
"Damn right I would." Jake reached over with one hand, sliding two fingers straight into her slick cunt. Emma moaned and rocked her hips, grinding down on his hand as he pumped them in and out, thumb rubbing her clit hard and fast.
"So fucking tight. You been saving this for me?"
"Only you," she gasped. "Drive faster. I want your cock."
They didn't make it another ten miles before Jake pulled onto a dark side road and killed the engine. He shoved his seat back and yanked his jeans open. His thick cock sprang free, already leaking pre-cum. Emma climbed over the console without a word, straddling him in the driver's seat, and sank down onto his dick in one smooth motion.
"Fuck yes," she hissed as he stretched her open. "Fill me up, big brother. Pound that incest pussy."
Jake grabbed her ass with both hands and thrust up hard, burying himself balls-deep. The car rocked with every slam. Emma's tits bounced in his face; he sucked one nipple through her tank top while she rode him like she was starving for it. Wet sounds filled the car, skin slapping skin, her juices coating his shaft and dripping down to his balls.
"Harder," she demanded. "Make me come on your cock."
He flipped her onto her back across the seat, one leg hooked over his shoulder, and drove into her with brutal strokes. Emma clawed his back and begged for more, filthy words spilling out. "That's it, fuck your sister raw. Come inside me. Fill my cunt with your load."
Jake grunted and buried himself to the hilt, pulsing hot and thick as he emptied deep inside her. Emma came with him, pussy clenching and milking every drop while she shook and cursed. They stayed locked together, panting, sweat-slick and messy.
After a minute she grinned up at him. "Round two in the backseat?"
Jake was already hard again. "Get your ass back there."
