YMBF, or better known as, Young Men Butt Fucking, is a notorious E-Posse of young men who like to proceed in indecent acts with one another through digital chat, via gc (group chat) or, vc (voice chat). Voice chats can also use video footage, where they record themselves doing several acts to please the other members in return for semen and acknowledgement.
Lame nigga: YMBF stands for "Your Mom's Best Friend" !!!

Real nigga: No it doesn't nigga
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