wow this board is as slow as ever.
to steal a question from /trash/
If you could make it so one character from fiction was openly black only, who would it be? Assume their story stays the same, they just at some point make it clear they are only attracted to black men, and their specific taste is misogynistic thug types. It isn't necessarily a focus if it isn't already, but essentially it becomes an undeniable aspect of the way they're written.
If it would somehow make it the story go differently (eg a romance show where she likes a non-black guy) then assume that it gets written in as a new story arc.