I'm sorry, so are you going to write an essay about kumi using bitch her new song and how its not ok??
If she calls herself a 'bitch' or uses 'yas bitch' meme (which is a bit cringy) then it's fine, because she can call herself whatever she wants to and it can be used in a somewhat appropriated endearing meaning. Still we don't know the whole context of the song yet.
People in this thread said that she's "our bitch" and that her cute cheerful side is a "bitch". These are deragatory uses and excuse me for not liking it when one of my favorite singers is being called a bitch.
How about that for an essay?