The act of removing the back of your whitey tighty strap and lifting it over someone’s head so that your buttcheeks make direct contact with their face. The perpetrator typically wiggles their butt so as to inflict the most butt assery.
One who is known to munch on the faces of butts, or an individual so irritating that you're almost positive that they munch on the faces of butts. See also: Ass hat.