Mushroom rat Rat

This anime make no sense at all why is the psycho girl more of the main character the real main character.Is she etheir abused by her parents or is she just born psycho pick a past. What was the point making two back stories when one doesn’t make sense at all . It’s like down grade art but worse and I thought the anime would get better but it got worse. The whole t y u n o plot twist was pointless.