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Well she was a tyrant of a child since she couldn't express her emotions correctly when she was younger, no one really helped her. Then she all of a sudden changes and becomes different they can't help but have that sense of caution for when she could snap back to her previous way of being even though we the readers know she won't since she's not the same person.
I'm sure as the story progresses they'll come to a better understanding and be better to her.
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Bruh … she became a tyrant because they didn’t give her any attention that she needed . Even the society keeps pressuring her and comparing her to her little sister . Her brother reacted like she wasn’t even there and they only see the little sister . Honestly , because of that , i came to hate the little sister too .
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Yeah … i know … i can actually somehow relate to her in a way … i keep getting compared to my sister when i was younger . People keep saying that she’s pretty and unique and everyone is kind to her …. Meanwhile , Im neither of that and i have this weird personality so people just naturally dont like me , bully me and avoid me like some bacteria … and my father has never been a father anyways . Kinda like her father but worse . So i just naturally hate my sister and father ^^ . So … i think it’s just weird that she reacts like that to her family and just accepts them like nothing ever happened.
I hate the brother in the Father matter what they do now because if they become kind I am not going to give the heck I just want her to get revenge on them even though I know she’s not gonna do that but like the whole thing was about the brother and the father not giving attention to her or helping ╮( ̄▽ ̄)╭ ヽ(`Д´)ノ (╬ ̄皿 ̄)凸 (︶︿︶)=凸(〜 ̄△ ̄)〜(๑•ㅂ•)و✧