mississippi sewage plant
When a female is receiving oral sex, rumbles forth with an almighty example of flatulence, and holds the rug muncher's head in place to bask in it's full flavoured glory.
Man 1: I went down on a girl for the I think 3rd or so time.. she purposely farted and held my face there.
Man 2: Ah yes. The ol' Mississippi Sewage Plant.
Man 2: Ah yes. The ol' Mississippi Sewage Plant.