Act of recieving a rusty trombone.. Aka the anal carwash...while continuing to urinate.. (rusty trombone= a hole being licked)
"While standing at a urinal in the office bathroom, jill came up behind me, unfastened my pants and continued to lick my anal porthole. The feeling was exceedingly intense. It's like doing the contrapositive of a blumpkin. (if ~q then ~p = if not getting head while shittig then not a blumpkin).". "dude she just gave you a Contra blumpkin...sick & twisted"