The Era Has Fallen, Use the Power of the Demon Clan to Unblock Me

His existence represents the entire demon civilization, and his footprints are followed by countless demon clans. He is known as the true ancestor of the demon clan, and he has never been forgotten even though he was ruined and destroyed. He once drank tea and enjoyed sermons with saints, and also fought against enemies from other worlds with the same hatred. Unexpectedly, he was betrayed by an insider. Because he could not be killed, he was sealed tightly. So, who is he? This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.