refers to using the other hand while masturbating.

From the episode of Family Guy in which Chris becomes popular. Meg asks Neil Goldman for a favor, and in return Neil is awarded the privilege of thinking about Meg in the tub later that night. In response to this, he says "I might even go lefty tonight....ooh, stranger in the tub."
Meg: Thank you so much Neil!
Neil: So this means I get to think about you tonight in the tub, right?
Meg: Ugh, okay Neil.
Neil: I might even go lefty tonight...ooh, stranger in the tub.
by Turd P Ferguson September 6, 2009
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