We had been driving for hours when my sister finally snapped. "Pull over, Jake. I can't take this anymore." Her voice was low and rough, the same tone she used when she wanted something filthy. I glanced over. Her skirt was hiked up, thighs spread just enough for me to see she wasn't wearing panties. Her fingers were already rubbing her shaved pussy, slick and shiny in the dashboard light.
I yanked the wheel and got us off the exit, tires crunching on gravel behind an abandoned rest stop. The second the engine cut, she climbed into the backseat and spread her legs wide. "Get back here and fuck your sister," she said, voice dirty and direct. "I've been wet since we left the house."
I shoved the seat forward and crawled in after her. The car was tight, windows already fogging. She grabbed my belt, yanked my cock out, and spit on it before stroking hard. "This is so wrong," she muttered, then took me in her mouth, sucking like she was starving. Her tongue worked the head while her hand pumped the shaft. I groaned and pushed deeper, fucking her throat until she gagged.
She pulled off, strings of spit connecting her lips to my dick. "Condom's in my purse. Put it on and fuck me before I change my mind." I rolled it on fast. She turned around, ass up, face pressed to the window.
I slammed into her from behind in one thrust. Her cunt was tight, hot, and dripping. "Yes, fuck your little sister," she hissed. "Pound that incest pussy."
The car rocked with every thrust. I gripped her hips and drove in deep, balls slapping her clit. She reached back and spread her ass cheeks so I could watch my cock disappear into her. "Harder," she demanded. "Make it hurt." I slammed harder, the wet sounds of her cunt filling the car. Her juices ran down my balls.
She flipped onto her back, legs over my shoulders. I folded her in half and fucked straight down into her. Her tits bounced under her tank top. I yanked it up and sucked her nipples while I kept pounding. "Tell me how much you love fucking your brother," I growled against her skin.
"I love it," she moaned. "Love my brother's big cock stretching my cunt. Don't stop. Fill me up." Her pussy clenched around me as she came, squirting around the condom, soaking the backseat. I kept thrusting through it, chasing my own orgasm. When I pulled out, she ripped the condom off and jerked me onto her stomach and tits, thick ropes of cum painting her skin.
We sat there panting, the car smelling like sex and sweat. She scooped some cum onto her fingers and licked it off, eyes locked on mine. "Round two in ten minutes," she said. "This time I'm riding you while you drive."
