Bwwm stands for black woman white man. A popular word used for black girls in a relationship with white men.
Search it on tumblr and you'll find several photos of white guys making out with black chicks.
White guy: Hey darling, you're looking Gorgeous as usual. <3
Black girl: Aww thanks darling. I love you!
White guy: I love you too. :)
Black girl: Let's post a photo of us on the bwwm page.
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