Mexican Halloween

A suggestively named fictional sexual position, referenced (often as a joke) in a TV show or movie, which then takes on a life of its own, and is created. A previously successful example is the Venus Butterfly; an unsuccessful example is the Guatemalan Face-hat.

Just put a name, place, or nationality together with any other noun, call it a sexual position, and people will either claim to have done it, or will invent it - Mexican Halloween all over again