Do it

Sam is rather surprised to feel his cock already beginning to grow hard in Monica's hand, and tries to look over towards their table. The crowds have now grown so much he can't see past the bodies most of whom were half naked and writhing with others.

Silently he nods and Monica gives him a smile, with one hand she slides down her panties, before moving to perch on the edge of a nearby table. She still hasn't released Sam's cock and she pulls him with it, guiding him into her waiting pussy and pulling him close against her.

They both gasp at the contact and within seconds Monica is lifting herself up and down on Sam's shaft, she leans in to kiss him and he can taste his own salty cum on her lips.

Feeling another woman's body writing against his own begins to push thoughts of Shelly out of his head and he begins to grow more into the motion, forcing his cock as deep into her as he can, drawing a scream of pleasure from Monica, enough to draw a little attention from some of the others around.

As Sam pounds away on Monica he opens his eyes to see Shelly, with her dress back on again watching the two of them. Their eyes lock and he begins to feel his cock ready to expel it's load for the second time, but also shame that he's doing this now with someone else.