welt pong

Uh....

My little brother and his friend are playing “welt pong.”  Basically it’s ping pong where the player on the receiving end of the serve turns around and pulls up their shirt to their neck, and the server nails them in the back with the ping pong ball.  
My little brother’s friend now looks like he has a red lifesaver imprinted on his back… and my bro just nailed him in the back of the head on accident.
So far my brother has been hit in the butt.


What the hell are middle schoolers playing?