Cover her ass

"Uhhhh!" You moan as you start cumming. You don't stop stroking as you start shooting you load all over her big, juicy ass. You just keep tugging as you're shooting bursts of cum everywhere. On her cheeks, on her back, on the bed, on her thighs, even a little on her asshole. She looks back at you lustily as you keep stroking it and try to get all your cum on her.

Finally satisfied you've unloaded everything you can, you start rubbing you still erect cock all over her ass.

"Oh yeah, rub it in, baby" she moans as she rubs her ass with you.

You give her a few playful slaps on the ass with your dick and then lay down next her. "That was awesome." you state, matter-of-factly.

"Glad to hear it, happy birthday!"