1 definition by oh tee gee

A fun game in which the participant stands outside a closed door where someone is sleeping. The player pulls out his penis and begins to masturbate. He must stand close enough to the door so his hand knocks on the door as he masturbates. The aim of this fun game is to get off before the sleeping occupants wake up and come to see what all the noise is. While the player technically loses if the occupant comes out of the room too early, the player may be able to get sex out of the occupant should it be an attractive female.
Guy 1: Dude I'm bored. What can we do?
Guy 2: Well we could always play knock knock.
Guy 1: Alright but this time I'm not going to my mom's door.
Guy 2: Fair enough.
by oh tee gee May 15, 2008
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