She is the nastiest bitch of them all. She does shit you would never believe. She would make out with guys you're fucking in front of you. She smells nasty. She tastes nasty. She creates a new level of bitchyness that blows away all other bitches. Often, she is a huge turnoff. More often, she is the girl that is all of the sudden not your friend anymore. Because she is suddenly so bitchy and evil.

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