In the warring states period of feudal Japan, the most beautiful shinobi in the world, Kagaribi, is given a mission from which no one has ever returned alive. His objective is to infiltrate the hostile territory of the Azure Dragon domain and steal both the heart and body of Rindo, its priestess who is said to carry the blood of the dragon god. Kagaribi, who has sworn to exploit those led astray by love and use romance as nothing more than a tool to rise in a turbulent world, sets out to deceive the priestess. However, his plan does not unfold as expected when he finds himself genuinely disarmed by her purity.

Rindo is the young priestess of the Azure Dragon country, revered for her spiritual powers and the divine protection of the dragon. Unbeknownst to her, she harbors a sleeping monster within her, a legacy of a tragic past. Her mother, Tsuyuhime, was married off to the land of Akutsu at the age of nine, and after that kingdom was destroyed by Azure Dragon, she was kept confined as a shrine maiden. Consumed by hatred and a desire for revenge against the ruling powers, Tsuyuhime called upon the dragon god and gave birth to Rindo as a weapon of vengeance rather than a child of love.

As Kagaribi attempts to flee with Rindo while evading pursuers like Shisui, the heir of the Azure Dragon domain who wants to see the priestesss bloodline end, he is forced to confront the truth of his mission and his growing feelings. Hotaru, a fellow kunoichi from Kagaribis village, grows suspicious that he might betray their country for Rindo's sake and tries to take the priestess herself, only to be defeated. Meanwhile, a smiling young executioner named Mozu and his black cat Oboro constantly watch Kagaribi, waiting to eliminate him if he shows any sign of betrayal.

The narrative arc follows Kagaribi and Rindo as they journey toward Akutsu, guided by a voiceless call from Rindos deceased mother. As the monster sleeping within Rindo begins to awaken, fueled by the hatred and sorrow passed down to her, Kagaribi is faced with a horrifying truth. When the transformed Rindo reaches out her hand, the shinobi who prided himself on using love is unable to take it, revealing the deep conflict between his mission, his survival, and the fate of a girl who was born only to destroy.