To bust one in one...This is the phrase used to describe a highly dangerous sexual manoeuvre which usually involves two people.Firstly, there is extreme stretching of the rectum and sphincter area of one of the two involved. After this initial stretching of the "asshole",the other participant shoves both penis and hand into the gaping hole and proceeds to masterbate excessively inside the rectum tearing the sphincter up horrificly causing a high degree of anal tissue damage. Of course if the stretching of the rectum is big enough more than just one person can bust one in one at the same time...
WILSON- Hey moe, fancy going upstairs stretching my sphincter apart with pliers and busting one in one?

Moe- I thought you'd never ask...PRESENT THEM
by Mr.scrotum October 15, 2006
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