Pee Bum Tap Ass refers to the runny shits that flow freely.Related to Mexican water and food or too much beer in one night.
Usually,the tap is stuck in the on position and can only be stopped with a Gerbil plug,massive amounts of corn,or Immodium.
Also associated with a shart,sharting
Fred:"Hey Bob,how's your diarrhea?"
Bob:"Great!No more tap ass,thanks for lending me your gerbil!"
Pedro:"Vote for Pedro!"