It is the little loop on the pant leg of a (usually) carpenter pants that is normally used to carry a hammer for convenience. Instead it is viewed as worn by an Alpha type held onto by a little bitch or beta type that worships the strap bearer.

ex. Similar concept to Prisons Breaks Theodore “T-Bag” Bagwell and his pocket

A jack off buddy (from 'cum' /'come', meaning 'semen', and 'companion'); a friend that you get together with for sessions of solo or mutual masturbation
Variant of: cumpanion (from 'companion' & 'cum'); jack off buddy & wank bud & JO buddy
Similar to: fuck buddy