In the Goryeo era, a mysterious assassin terrorizes the land. Whispers in the dark alleys claim the assassin is a woman, but her true appearance remains shrouded in enigma. Some say she is as beautiful as a fairy, while others swear she is as hideous as a troll. To the oppressed, she is a ray of justice; to the wicked, a storm of retribution. Known by many names—Death Fairy, Grim Reaper, Blood Flower—she strikes fear and hope in equal measure. But the burning question remains: who is this elusive woman?