This is probably one of the only series and relationship where you should understand their dynamic of calling eachother dad/babe.
They were the only ones that loved eachother.
Sure, it's twisted, but I don't see y'all pointing out all their abuse and rape they've been forced to endure.
Their weird incest dynamic is the least worrisome problem, it's literally the only thing good they have going for eachother.
You guys need to get your priorities in check.