The house was dead quiet when I slipped into my sister's room just after 2 a.m. She was already asleep on her stomach, one leg kicked out from under the sheet, her bare ass barely covered by the thin cotton. I stood there for a second, cock already hard in my boxers, watching the slow rise and fall of her back. Then I climbed onto the bed behind her.
I pulled the sheet down slow. Her pussy was right there, smooth and warm. I spit on my fingers and rubbed her slit until she was slick, then lined up and pushed my cock in with one steady thrust. She woke up with a low moan but didn't tell me to stop. Instead she pushed her hips back, taking me deeper.
"Fuck, yeah," she whispered into the pillow. "Harder."
I gripped her hips and started pounding. The bed creaked but we didn't care. Every slap of my balls against her ass sounded loud in the dark. She reached back and spread herself wider for me. I could feel her getting wetter, dripping down my shaft.
When I was close I pulled out and flipped her onto her back.
She spread her legs immediately. I slammed back in and fucked her until she came, her cunt squeezing me tight. I followed right after, pumping thick loads deep inside her while she bit my shoulder to stay quiet.
We lay there catching our breath, my cock still twitching inside her. Down the hall we could hear Mom's bedroom door open. Neither of us moved. We just waited, breathing hard, ready for whatever came next.
