The objects in Shu Jie's family personify daily life (but the protagonist is not Shu Jie). The eraser represents pencils, rulers, ballpoint pens at the beginning... Are they all good children? Something strange seemed to appear later? Or is the originally cute girl spoiled?
Rubber: "Everyone is not a bad person, right? Although they are all a bit strange..."
PS: I'm a novice at writing, especially novices who don't have more than 2.0 In the synopsis.