Refers to how full one's bladder is.

If one's bladder level is high, they have to pee. If it's low, then they don't have to go.

However, if one's bladder level is over 9000 then they are in dire need to go pee, or they are most likely dead due to pee replacing most of the very blood in their veins.
Johnson: Mr. Grate, I must go to the bathroom.

Mr. Grate: Nonsense! I don't believe your bladder level is high enough.

Johnson: I have a bladder level of over 9000.

Mr. Grate: ... WHAT ARE YOU WAITING FOR?! GO!
by uh... bob. April 28, 2009
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