Last dungeon of defeat - Humiliation for female warrior Erina

The brave was defeated. - The Demon King who threatens humanity appears, and the invasion of monsters has begun for more than ten years. - Monk’s Irina was a member of a brave group heading to the Demon King’s Castle. - The party boarded the Demon Castle, but without reaching the Demon King, it was annihilated by one of the four heavenly kings.