upon finishing anal sex when the male pulls out and has poop residue on his mushroom stick
Friend 1: Did you have fun with Heather last night?

Friend 2: Yea we had dinner and screwed and she let me put it in her backdoor but when we finished I had to go clean off ASAP because she left me with a rusty mushroom.
by SunDiablo August 7, 2013
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