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The act of using Mermaid Man's belt of power, on the Wumbo setting, to enlarge the male genitalia and then proceed to have anal sex for maximum asshole enlargement.
When Trisha least suspected, i dirty wumboed the shit out of her and now she's paralyzed.

Don't ever dirty wumbo anyone, thats how my sister died.
by beefyking March 18, 2013
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