1 definition by M Smiddy

A huge walking erect penis, who steals others penises so that it can get bigger and harder. Be careful though unprotected sex attracts the beast.
Dude last night i banged Sara. -man 1
Did you use a condom? - man 2
Nah... -man 1
Damn dude watch out the Boner Monster might come for you. -man 2
by M Smiddy July 21, 2011
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