When the gas from a
woman's fart enters her
vagina. The term is derived as follows: Fart UP pusSY. Not to be confused with a queef, which describes the expulsion of air from a
woman's vagina.
If you are a girl, and you are wearing tight jeans, sitting in your car, and you have to fart...if you are sitting, you are
already in a "few viable exits"
situation; so sometimes the
bubble goes FORWARD, and slips up your pussy; voila! Fupsy!!