What is a upper decker?

An upper decker is a prank that involves deliberately defecating in the tank of someone's toilet instead of the bowl. It is considered a highly inappropriate, disrespectful, and unsanitary act. The result is that every time the toilet is flushed, the water from the tank releases contaminated water into the bowl, causing an unpleasant smell and making the toilet unsanitary for use.

This prank is typically done as a means of revenge or to cause significant inconvenience to someone. It can be difficult to clean up as the tank may need to be emptied and thoroughly disinfected.

It is important to note that engaging in this type of behavior is disrespectful, immature, and can potentially damage personal relationships or result in legal consequences. Performing an upper decker is widely frowned upon and not considered an acceptable or responsible course of action.