The main goal of the mc is to make a harem but his/her harem are full of powerful beings like an avatar of a god, a clone, and a reincarnated that needs to die in order to make its real body breakthrought to a higher realm. To mc's perspective they are just people he/she helped then married and what he didn't expect that theyr not the real body and are only a small part of their real body. And while he/she were having fun with his/her wifes, he/she was getting affection from their real body slowly until all of his/her wifes merged into their real body.