@yumian
she was abused for years that made her developt low self-esteem and some traumas, there are habit because of trauma that hard to get rid especially if that involved with her family and their abuse
like she said before, she hate that side of her, she want to change, but it's not that easy because of that traumas, she should overcome her traumas first, Kudou and Yurie-san helps her hold herself little by little
the reason why she can't talk back to kaya that time because she still not developing herself futher for now
there will be character development, but it seems it was a bit slow to matching the tone of the story