Come back and bite one (on the ass, arse, butt etc.)

If something or other comes back and bites a person, then that person is guilty of saying or doing something in the past that has triggered unfortunate consequences. The origin of the expression in this sense appears to be American from c.1950, but was soon taken up by British English. Since then, refinements like 'ass', 'arse', 'butt', 'bottom' bum', etc. have been added for more emphasis.