Roland, the world’s strongest swordsman, spends his days fighting to defeat the Demon King. His emotional support is his beloved girlfriend, Felicia. However, due to the Demon King’s curse, she is transformed into a monster. Felicia loses her sense of self and attacks Roland. In despair, Roland fights her, and the two die together. As his consciousness fades, Roland hears a voice: “You must not die here…” And then Roland is revived. In place of the arm he lost in the battle, he obtains the arm of Felicia, who has turned into a monster. This dark fantasy begins, in which he seeks revenge with the arm of his beloved.