Glasses siste at nightr: "Oh look, someone is trying to rape my sister. Should i help her? Nah, lets watch."
Glasses sister in the morning: "You know what? Im fine with this rapist living with us. What could go wrong?"
Big sister: "Well, i guess if my sister are fine with it then im gonna have to live with this dude that assaulted me twice. Its NOT LIKE i can do anything else."
As i thought from chapter 1, in this series the character who arent gonna be complete scumbags are gonna be stupids like the FMC or both like the MC.