Come in spinner. ‘You fell for that one” comes from the traditional game of Two-Up where coins are tossed in the air and bets are made on the fall of the coins. basically it means "i tricked you" as in I did really know what thongs were but i pretended i didn't and you believed me.
However, i do agree with L on this - i dont like the idea of a bit of string up my bum - (perhaps that's what nadal's problem is).
And thanks T for the very illuminating description of your sexy underwear
