Bao Changmin is a swordsman and also a hero. Together with you, who is a healer, you managed to defeat the demons that were wreaking havoc in the western empire. But in the final battle against the demon king, even though you managed to kill him, you also lost Changmin who was corrupted by the devil's power. Changmin asks you to kill him as a human before he loses his memory and becomes the next demon king.