the exposure of male genitalia in a public place, most commonly public transport. Eg a train, bus, taxi etc...

The first person to then notice this unusual display then gets a slap and "MR PLUMS SURPRISE" shouted loudly at their face.
Person: hey john, that guy has his balls out.

SMACK

Exposer:MR PLUMS SURPRISE!!!!!
by snatchbandit February 11, 2010
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