God Slaying Demon King vol 1 back

After centuries of war between demons, the world was finally united under the overwhelming power of Hiram, the strongest demon king in history. No demon could match him, but even the mightiest king can not so easily defeat a god. When Hiram defied the demon god, he and the deity engaged in days of fierce battle where, in the end, he was cut down by divine punishment. The demon king, however, is never without contingencies! Hiram cast a spell that, in the event of his death, would reincarnate him years later with all his powers intact. Only this time, he would be born as a human, a race the demon god has no power over! With his life restored, Hiram begins a grand adventure to find the demon god and kill him once and for all!