Convince her to stay

"No no no, I'm going to show you a good time tonight," you insist. "I'll go get you a drink at the bar." You walk up to the bar and fight your way through the crowd. You see a big line at the bar and decide to relive yourself quickly while you wait. Finding the bathroom also crowded, you duck outside the back door to a small alley you know is often used for quick pees. When you open the door however, you hear slaps and moans coming from down the alley. You squint and make out a man pounding a woman from behind. The woman has her hands and face on the wall, standing up, with her hips being held by a large man voraciously thrusting into her from behind.

The man has his jeans around his ankles and his shirt on the floor, while the woman's short skirt is hiked up around her waist, her panties are on the floor still around one of her stiletto heels, and her shirt is lifted exposing her bare midriff and tits which are poking out of the top of her bra.