
What happened to the first girl with black hair I don't understand it I'm confused right now

Spoiler
I don't remember since it was quite a while ago when I read it but remember in the beginning it showed her on all fours running away? Well, that's her true form and she can't control her urge to kill (especially when she feels threatened). So the glamour or her disguise not only changes her appearance but also stops her from going berserk. I dont think she's a demon but I'm not entirely sure because I read the raws and I don't understand Korean. My hypothesis is that she's just apart of some beast clan or something.
But he doesn't deserve him
Everything he did to him was no way for acting like that, I hate him sorry
I hate him so much even in the entire manga