I wouldn't be surprised if Oneiros got reborn as a demon a.k.a hypnos. Remember Hades and Poseidon? In the story, they both lost human faith and had no choice but to be reborn. Gods get weak if they dont have much believers but they can regain their power. Demon cleric also mentioned that he found nothing about hypnos and hypnos himself admitted that he does not remember much of how he ended up in the demon king army. Its possible that the black version of himself got out when demon cleric woke him from his slumber (remember when he got cursed because he woke hypnos from his slumber?) Its just a theory but maybe hypnos is currently incomplete. If he merges with his other self, he might regain his memories as a god
I wouldn't be surprised if Oneiros got reborn as a demon a.k.a hypnos. Remember Hades and Poseidon? In the story, they both lost human faith and had no choice but to be reborn. Gods get weak if they dont have much believers but they can regain their power. Demon cleric also mentioned that he found nothing about hypnos and hypnos himself admitted that he does not remember much of how he ended up in the demon king army. Its possible that the black version of himself got out when demon cleric woke him from his slumber (remember when he got cursed because he woke hypnos from his slumber?) Its just a theory but maybe hypnos is currently incomplete. If he merges with his other self, he might regain his memories as a god