On the official Warrior Cat Forums, a SMBU is a Super Message Board User. These users are possibly pedophilic individuals who enjoy wasting their time on message boards with hundreds of thousands of post talking to barely pubescent children.
Look, look at that SMBU. I bet she's some fat fuck that eats cheetos all day.
by lolyoloswag420 February 03, 2014

5 Words Related to smbu

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