wheeze okay I don't even know how to respond here without just explaining literally her entire character and backstory so uhh I guess I'll do that as short as I can. TL;DR Kaoru has been a very powerful psychic since she was very young without realizing it, powerful enough that even average humans with no supernatural talents could sense something off about her. Naturally this meant everyone she ever interacted with was unnerved and freaked out by her and didn't even really know why. She was bullied a lot, people spread rumors about her being a witch who could kill with a look, her parents rejected and feared her, etc etc, which all culminated in her mom calling for a literal demon hunter to come and murder her because she thought her daughter was The Actual Devil. Kaoru was like. MAYBE 12 or 13 when this happened.

SO she was like...okay...I guess if everyone thinks I'm a monster I'll just be a monster then!!! And she gathered up a group of lesser psychics to serve her and started sending them out to hunt down and kill every other magic person they could find because uhhhhh life is pain and they're better off dead, probably, and honestly, they should be THANKING her for SPARING THEM the SUFFERING OF LIFE [citation needed]. But really it's mostly because she's an angry, angry, little girl who kinda just wants someone to step up and kill her already.

And now in Aurora she doesn't even have any of her powers so like...lol.