Wow, I really hate Yuko. She kills all her friends, tries to kill an innocent guy, and the entire time refuses to listen to a word anyone else says, or even think. She's like a baby.
I really hope she manages to understand something next chapter. At least let her recognize the reality of what she's done and stop pushing this devil delusion. Then I want Mitsuko to kill her, so she understands that anyone can do evil.