“Pin-and-girdle” and “prick-the-garter” are two names for the same game, in which a belt or long piece of cloth is doubled and then folded a number of times, then held in the swindler’s hand. The flat is given a pin and bets that he can stick the pin in the belt at the place where it was doubled. Of course, the game is rigged and he can’t. This game dates back a good long way. This game has many names and variations, but one of its earliest names was “fast and loose” (attested 1578, and using “fast” in the sense of “immobile, fixed” as in “stand fast”), which is where the idea of “playing fast and loose with” something or someone comes from!