I think there's something going on with the childhood friend. They wouldn't introduce her for no reason she might have some type of different power than the zodiac girls do maybe her own unique powers
So he wants to respect her and get to know her just to have sex with her then gets all sexually frustrated now that she pushes him away when he tries to go for it. The mc is garbage
I think the old (dad) is going to do something to them and the new dad is going to protect them but might end up getting hurt. Which is going to draw them closer to the new dad.