>>66230236GBF spoilers, obviously:
Nier is completely fucked in the head. She craves love and affection, and is jealous that her parents treat her talented younger sister better than her. So she seduces and murders a bunch of men to master some forbidden magic to impress her parents. It obviously doesn't work and so she murders her sister and her parents in cold blood. She then falls in love with the MC, or (you) in this case.tl;dr: Nier psycho yandere, like REAL PSYCHO HOURS.
(I don't know if Hime actually knows Nier's full lore, since the requirement to unlock her was absolutely autistic back when I played)
