When you invite all of your friends to a smack party and they think it's a party where you all take smack. But when they turn up they realise it's a mass spanking of ass where everyone spanks each other's arse.
When you suck your own dick while your girl licks her pussy while listening to Stacy's Mom by Fountains of Wayne and record it to send to Harvy Weinstein
Guy 1: John looks happy today
Guy 2: Well, I heard last night his girlfriend agreed to have a Hammy Sammy Harvy Stacy Party