The term is a slang used in New Zealand which describes one whom stimulates one's or own genitals with hand. The old boys refers to the hand beating the testicles while stimulating the penis.
Playing Solo: Braxton's brother Ronald told me that he walked into Braxton's room and he was beating the Beating the old boy's

Playing friends: Hey Ragsag you want to go somewhere private to beat the old boy's
by D_strikes September 18, 2017
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