Maou to Odore! - Legend of Lord of Lords

You wake up in your room and find a woman, whom you don't know, standing there. She says that you are the reincarnation of her liege. The Demon Lord who was sealed away centuries ago by the goddess of the land.

She tries to give your memories back but fails and gets upset. Then she decides that to awaken you, she must take you to the places where parts of your sealed power should be. Threatened by her, you follow her. In the first dungeon, you save a priestess who thinks you're the Messiah coming to save the lands from evil...

[Edited from a forum post by OLF]