Stands for butt cheek fucking. Basically means sticking your penis between some chicks butt cheeks and fucking the shit out of her.

AKA - titty fucking her back door.
That nappy hoe was on her period, so I BCFed her.

Hey bob, I'm going BCFin' this weekend. Wanna come?

That bitch took a shit when I was BCFin' her. Turned into a fucking chili dog.
by WikiPete January 24, 2012
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