I also agree with the others saying that the father is the contractor. As we've seen so far, it's not that he doesn't entirely care, he cares but refuses to accept it because if some sort of tradition that he can't act like a normal father is this family (I feel like there's more to know about that subject). So far he's only been neglectful towards her but otherwise provided for her accordingly (no verbal or physical abuse) of course the neglect is still incredibly wrong and irredeemable (tbh I hope thier relationship gets better in the future, not for them to have a close father-daughter relationship, it's extremely hard after everything he did, but at least anything better than this) I suspect mind manipulation magic or something similar because he acted close to the other daughter even though he cares so much about the 'tradition'. Maybe he woke up from that manipulation later (maybe seeing his daughter die, or the other one's actions, or the magician interfered) and it made him want to go back in time, but reserved the memories for her because he thought he didn't deserve a second chance, or that she deserved it more, something like that.