Rim Breaker
When you need a shit, but you have to hold it in for a couple of hours, and when you finally get to release your bowels, you hear and feel a thud as the shit plops through the water and hits the porcelain on the toilet, resulting in a vibration, and a person in a state of disbelief
Man takes shit, shit falls out, the force rips through the water and gives the vibrations of a double Sub-Woofer sound system, practically (and sometimes literally) breaking the rim, hence Rim Breaker

chocolate log courtesy flush turd burglar