To masturbate, that is, stroke the genitals for sexual pleasure. Usually it refers to men as their penis is shaped like a snake, and a shaking action ensures orgasm.
LinktheChristian:I'm going to go home and clean my sword.
GanontheDevil:You're going to shake your silly snake!
ThaddeustheTolerant:Elves don't have a need to jerk something that small.
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