The act of smelling or noticing a person deficating, and seeing their poopy and getting a colossal erection. This can also be used when your having sexual intercourse with a persons fecies.
CJ says :"Do you smell that? I think someones shitting."
Matt says: " Yea yo, i think im getting a Fecies Boner. Its starting to rip through my jeans."

Fecies Boner
by Aggressive Ass Play Lover July 25, 2011
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