dropping a grumpy
A polite way of saying that you’re shitting a massive turd. One of which causes you to make an angry face.
After eating that second helping on taco Tuesday, Jeff was in the bathroom for a good hour dropping a grumpy.
Dropped a Grumpy
Dropped a turd; passed your bowels
The party was raucous. So many stoned people! Somebody even "Dropped a Grumpy" on the bed!