You make her like it, she cums, you don't cum.

You lay Jessie down on the couch on her back, her dark hair spilling out over the couch behind her, and slide your hard, thick cock up her pussy. Your girlfriend's hot little sister arches her back, taking your shaft deep, and moans as you fuck her. "Oooh, fuck! Oh yes! Oh, fuck, yes!" Jessie reaches up to grab hold of your ass. You put your hands on her tiny tits, and pinch her stiff little nipples.

Jenna watches the two of you fuck, feeling her own tit through her t-shirt, one hand pressed between her legs. "Ooh, yeah baby, fuck my sister. Fuck that little pussy hard."

Then you feel Jessie's pussy constrict around your cock, flooding with her wet, juicy, teen orgasm. She moans and writhes and bucks, cumming hard. It's so good, but you don't cum yet. You slide your cock, still rock-hard, out of Jessie's dripping wet pussy, and pull her up to kiss her sweet mouth. Jessie kisses you breathlessly, sweaty, panting. Your girlfriend looks so turned on, staring at your hard cock slick with her sister's pussy juices.

(Mark +1 xp for making her cum)