Responses
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If the adoption gets cancelled they can marry legally. It's not incest if that is the case. Also the FL and Eugene spent like 3 years (?) or something together so there is not the same ''siblings bond" like Hari has with the other brothers. I guess she sees Johann now more as a brother than eugene, after all she grew up with him in the same Household longer. Guess this is what the Author is aiming for if Hari&Eugene get together for real.
no matter how u think about it... its disgusting they were brought up as siblings:/