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