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1 definition by Daz Jenas

Rectal Ball Insertion. When a guy manages to get his testicle into a girl's rectum. To this day, there are no reported cases of the RBI.
We were getting bored with our normal routine, so last month I decided to go for RBIs.

It really, really hurt my balls but I got them in there. I'm up to 5 RBIs this season.
by Daz Jenas December 17, 2009