I guess the DEV thought it was a great idea then couldn't think of a way to continue the story line, so they said, "fuck it" and had her seduce the MC. That's the way so many of these DEVs go. "If you can't beat 'em fuck 'em!"
In the latest update, friends of the 3-daughters is coming to see them. I would put money on it that she will too, find a way to get romantically involved with the MC. I'm hoping that's not the case, but the way this story is developing, I'm almost sure that it will happen that way.
So, I'm not sure if I should be excited to finish the game or not. Sometimes, I just want a true daddy simulator, because I miss my daughter IRL, and playing a VN is the next best thing to her being here.