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When urinating in a public bathroom, and another dude comes up and takes the urinal to spots down, thus leaving the one in between empty.
Tom: "I was pissing in the library and this other guy comes in..."

Eric: "..Dude, please tell me "Urinal Rule'?.."

Tom: "Of course man, unwritten dude code!"
by bluefalcon916 December 06, 2008
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