Not gonna lie, I usually like harem routes, BUT when you had however many chapters of him and Marika, I can't help but beg for this to not to turn into a harem. Marika is waifu material and he better not fuck it up. If anything and I mean anything, he might have to bridge the gap between demons and humans and if that is the case, I would only see it as he must marry 1 demon so he has a bride of both races. And if that's true then I can only see him shacking up with the Heavonly King of Earth (forgot her name). Not this Wind king because she clearly has the hots for his adoptive brother.