An obscure body modification practice, but growing in popularity and often performed by unlicensed surgeons in the backs of customized vans. The procedure involves the switching of the vaginal and anal canals inside the body while leaving the outside of the orifices intact and unmodified. After the surgery is complete and the patient is fully healed the girl will be able to poop out of her pussy and get impregnated through anal sex. Not to be confused with the BV flip.
person one-"her twat tasted so bad she musta had a BV flip, cause that slizz tasted just like shit"
person two "I think you are confusing a BV flip and a BV switch again"
person one-"sorry sir"
person two-"just dont let it happen again"
by Legodogel May 2, 2012
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