When a man fucks a woman/man's mouth while simultaneously shitting on the chest of the fellatio performing participant.
Jimmy's girlfriend was giving him head while Jimmy had a serious case of the runs (too much cheap beer). At one point Jim could not hold it in and in the middle of the mouth-fucking, let his bowels loose all down his girlfriend's chest; giving his partner her first ever Las Vegas Oil Change.
by Pubes Monroe November 2, 2012
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