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1.
When some one is having anal sex and person taking it up the ass shits.
Mike mudfucked her last nite
by MR productions August 13, 2006
 
2.
(n/v)During anal, the receiving partner has not properly washed her anal cavity and leaving behind pieces of feces which the male encounters.
(n)My girlfriend and I had a major Mud Fuck fest. It was nasty.
(v) I Mud Fucked my girlfriend.
by streetusa710 July 16, 2008