Keep Watching

I calmly walked into her room. Lucy was glaring at me the whole time. Sam looked surprised and had stopped fucking her.

"Well, well, well. What's going on here?" I said as I sat down on the bed.

"I…errr" Sam stuttered "I-I should probably just go" he began to lift off the bed and pulled out of my sister.

"I don't think so" I said suddenly, I pushed down on his ass forcing his member back into my sister. She gasped and shuddered at the sudden unexpected intrusion. "You're going to stay right here and fuck my little sister sensless and I'm going to watch"

"What?…I errr" he stammered

"And if you don't I'm gonna tell my parents what a little perv you are. I've seen you watching me while I change or touch myself. I wonder how many times you've seen me naked, or how many times you've gotten off watching me" I said in a sultry tone.

"Please don't tell anyone" he said quickly

"If you don't want me to tell, you'd better do what I say" I said

"Ashley get out of my room you're being rediculo…" my sister was suddenly interrupted as Sam resumed fucking her "ooh…aught…Sam what are yo…aauugh.…" my sister tried but she could resist for long. "Ooh, fuck me" she whispered.

"I knew you'd enjoy this" I said

Lucy ignored me and focused completely on Sam, "fuck me harder, harder" she moaned. I watched as Sam began to thrust deeper into her and Lucy's moans got louder.

Soon she was nearing her climax, "oh god…I'm gonna cum…I'm gonna…aahh…I'm cumming…AUUGH IM CUMMING, IM CUMMING…"

Sam began to pull out, but I stopped him. "Oh no" I said "you're gonna cum inside her". I put my arms around his chest, causing my tits to press up against his back, and pushed my crotch against his ass, forcing his dick back inside my sister.

"No" my sister moaned meekly as Sam filled her pussy with his seed. I watched her face while she squirmed. It was clear that she was struggling not to enjoy the feeling of the warmth now spreading between her legs.

They were both breathing heavily as they lay there trying to recover.