You are Adell, a young man who is the last human in the small town of Holt. Overlord Zenon has gradually been turning everyone into demons and stealing their memories.
As Adell, you attempt an assault on Zenon himself, meeting some very interesting people along the way. A botched summoning brings the daughter of Overlord Zenon, Rozalin, and binds her to you. Her servant, Tink, was turned into a frog and wants revenge. Your brother and sister, Taro and Hanako, join you in your travels. A ninja you find in the Colosseum, Yukimaru, decides to accompany you to destroy Overlord Zenon. Finally, a Demon Lord that you mistakenly set back to level 1, Etna, demands to travel with you until she regains her levels.