Someone that performs a hand job on you for sexual gratification. May be a girlfriend, boyfriend, relative or complete stranger.
I’m gong to see Rachel after work. She’s my go to arm butler and I need to nut one out.

Your sister has been my arm butler for a while now. She’s getting good at it.

My uncle is a great arm butler when there’s no alternative.
by Eaton Holgoode February 5, 2018
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