Helicopter

This is when a man or woman sticks their ass as far up unto the air as possible. Then a second guy proceeds to insert his massive shlong into the ass of the first person. The person on top tries to stay as horizontal as possible while using their arms to spin themself around like a helicopter blade.

Guy 1: Hey want to Helicopter on me?
Guy 2: No dude that's gay
Guy 1: Want to play Soggy biscuit instead?
Guy 2: Yeah, sure man!

Slap

The precursor of the phrase "Yo ass cheeks"
There are no other uses of the word slap, but it is said to mean "To swiftly swipe your hand over something in a sexual manner.

Wannabe Gangster: Oh yo my hoe I'm boutta slap yo ass cheeks
His GF: Make sure to do it hard, daddy!