Responses
The boy has become a fanatic his mind is beyond saving girl on the other hand seems to doubt everything they are doing and is probably only following the boy
I'd say it's more of a feeling of guilt and being indebted.
Like growing up in an abusive household and still loving your parents because they're family.
She was saved like her brother so she feels like she has to follow their master even though she feels like his methods are wrong.
I agree that her brother has definitely turned into a fanatic and is wholeheartedly following him on his own.
I don't know but i feel like the dark hair girl is redeemable, she has that looks unlike the boy