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2.
being the third man to penetrate a girl and being forced to fuck her up the ass because the mouth and pussy are already taken
Ryan: How was it with Janie last night
Eric: Terrible I was the third man in
by Lionboy January 10, 2008
 
1.
The third person to enter a fight, almost always escalating a one on one altercation into an all-in brawl.
Steve was handed a game misconduct for being the third man in the altercation.
by JohnTan February 04, 2009