huh, interesting
i think she herself knows she's a demon and that she has a time limit so she wants to drag everyone down with her when she dies :0 what a villain. also she mentions she wants to get revenge for her mom and that means getting revenge on the duke. what the duke loves most is money & power, so she pretty much wants to take everything away from him ╮(￣▽￣)╭
No. Cossette is not a demon, its a DEMON using cossette identy, because cosette is literally dead like she still in her mothers womb she died. so the demon just want the end of the world because it a demon no other reason. The demon just played the fl family since if the fl died less obstacle for the end of the world. He disguised as the dead cossete who is actually alive to cosette uncle (sole survivor of their family since everyone is dead) who wants revenge to the fl family not knowing he was just being played by the demon.
Does it have novel?
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cosette is demon, she wants to end the world idk why but she just wants to end the world. But her whole plan will ruin (≧∀≦)