Let me guess...
Soffione turned against god because he doesn't allow monster-human harmony and called it blasphemy, the party then meet Safione and had a long talk/fight and then convinced that the god is indeed one of the obstacles of monster-human harmony and turned against him with Soffione, oh and also, Safione become part of the harem and the elf queen from before somehow joined the fight and become part of the harem as well
Bonus points if the Demon corps is actually a good person and is also striving for the harmony and thus decided to join the MC as well