When you masturbate while shitting. Preferably done at a friend's house, while texting someone else on your iPhone.
Sean: So I just went to bust a set
Jon: What?
Sean: Set.
Jon: -What-?
Sean: Masturbating while shitting!
Jon: What?
Sean: Set.
Jon: -What-?
Sean: Masturbating while shitting!
by the semen banditz February 20, 2009
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