The Greatest Demon King in the Other World

Lucifer,  who is said to be the strongest and most evil demon king… However, he was the hero who tried to protect the people who were abandoned by God.

He went to sleep to heal the wounds he had sustained in his battle with God and awoke a thousand years later.

What he saw was a peaceful and prosperous city. No longer did he need to protect the people. People began to walk on their own feet. From now on, he would enjoy the world created by the people, not as the Demon King, but as just another human being.

But he doesn’t know. …for a thousand years, his subordinates continued to train him to become stronger and more powerful, in preparation for when the demon lord awakened. There’s no way an outsider like him can live a normal life.