A dance and antic when a dancer pulls his pants down to show his/her bare naked ass and dances
See Bare Butt Boogie
Derives from the anime Shin Chan
Shinosuke Nohara: Ladies and Gentlemen come buy a sasuage and see the dancing ass boy. Ass Dance, Ass Dance, woo woo!
Ass Dance: n. When an obnoxious person (usually drunk or stoned) dances to put emphasis on their state of Assholeism.
Cooper's "Ass Dance" on the pic-nic table, the boy was indeed a drunken fool. A naked drunken fool.