ok, so from what I've read the dad was being controlled by a demon. If you remember in the beginning the girl that replaced out MC was a demon. She put the dad under some hypnosis spell so he could not think straight. He has always loved his daughter but did not know how to express it because of how he was raised. Anyway, when the daughter died the father finally got out of the hypnoses and could not bear his daughters death and the all the wars happening all across the country. He makes a deal with a demon to turn back time to when his daughter is (well I forgot how old she is but ya) and that's why he remembers some of what happened in the past.
Ok he's not that bad but the father should have known to idk at least visit your daughter maybe once when she fell down the stairs. Like he might just be really stupid but I think that it's a pretty easy thing to do regardless of how you were brought up.
Also from the spoilers in NovelUpdates, I dont think he's being controlled by the demon Xylade
Oooooh that makes sense especially if you remember the parts where he's like "I just want my real daughter" or that scene with "I would like to name our first daughter Cosette" and where he thinks that she's not his child
SPOILER
ok, so from what I've read the dad was being controlled by a demon. If you remember in the beginning the girl that replaced out MC was a demon. She put the dad under some hypnosis spell so he could not think straight. He has always loved his daughter but did not know how to express it because of how he was raised. Anyway, when the daughter died the father finally got out of the hypnoses and could not bear his daughters death and the all the wars happening all across the country. He makes a deal with a demon to turn back time to when his daughter is (well I forgot how old she is but ya) and that's why he remembers some of what happened in the past.