An acronym for 'Yay, a sex slave!' Anyone who says it is instantly part of the sexslave movement, whether they like or know it, or not, and whoever hears it instantly dies of cringe.
Friend 1: Hey bro, you want to go to the nudist beach?
Friend 2: Yass!
Friend 1: *dies*
*years pass as friend 2 is protesting in the sex slave movement*
Parents: WHEN DID WE GO WRONG?