Getting too much

I looked at her pleadingly. Who knows whether I was begging her to stop or to finish me off… Suddenly my jaw fell open and I felt my climax swirling up. Monica didn't let up, and the first spray of cum shot out of me and into my boxers. I clamped my mouth shut and did my best to stifle a groan. She kept tugging at the base of my d*ck, squeezing me as it pulsed with each new spurt into my clothes.

Shutting my eyes in ecstasy and embarrassment, I felt myself soak my underwear, cum trickling down my thigh. When it was all over, Monica invisibly removed her hand from my lap and left me alone. I sat there in between both girls, completely humiliated. I just let my girlfriend's little sister jack me off… right fucking next to her. And I'll be damned if it wasn't one of the best orgasms I've had.

After the movie was over, Vivian was the first to get up off the couch. My heart had been racing a mile a minute, praying that she didn't kn