A washroom game where the one who is it, leaves a poop in the toilet without flushing*. You become it when you walk into the washroom to find a poop that has not been flushed. You must then continue the cycle of poo-tagging, either in a new location, or right away.
*Bonus kudos for leaving a poop that isn't covered up by toilet paper. The grosser, the better the revenge.
Bro, I got poo-tagged today at the mall, now I gotta leave some poop at a McDonald's to hopefully poo-tag some fat-ass after his big mac.