Amy milks your cock with her pussy

Amy gets on top and straddles you on this very public beach. Her wet tight pussy is lowered down all the way to the base of your cock, and she puts her hands on your chest and starts riding you hard. Amy does her very best to use her pussy like a fleshlight on your cock, bouncing up and down as if to jerk you off with her pussy.

Rachel squirms, poorly hiding that she wants in on the action. She looks back at you two again and again, but can't swallow her pride enough to actually ask and join. You notice her, but ignore it because it's fun to make your lil sis mad.

You really start clapping Amy's cheeks, thrusting hard into her as she bounces hard into you. You two intensely fuck like rabbits, as Amy does actually have the hots for you, and it gets really hard for Rachel to ignore.

Amy's pussy feels incredible, but you're still a while away from cumming. You fake a "Aw fuck I'm gonna cum soon" while looking at Amy, and out the corner of your eye, you see Rachel turn back and look at you. Her face scrunches up as she thinks hard of an excuse to join before it's too late.

Amy leans in for a passionate kiss, which you two get lost in as you get acquainted with her insides. Rachel feels her window of opportunity closing and says, "Amy, I know you've had enough of this jerk. I'll take him off your hands 'cus, uhm, I just know you have to be so annoyed with him fucking you like that. All annoying, fucking you that deep and hard and..." She trails off.
Literally no one believes Rachel's lie and you and Amy look at her, dumbfounded at how it was such an obvious excuse to get some dick to herself. Amy almost looks like she's feeling bad for your sister as she hops off your cock. "Suit yourself," says Amy, and you move to get on Rachel's backside. A horny smile flashes across Rachel's face before she tries looking pouty and annoyed again.