In the world of Jiuyou, Shen Zhenyi, the third son of Abandoned Sword Villa, acquired the ancient martial arts "Wan Zang Sword Sutra", which attracted the coveted of martial arts in the world. The leader of the Demon Sect, Minyiren, fought with him for the sword, but the third son disappeared. A year later, Abandoned Sword Villa reopened the mountain gate, and Shen Zhenyi asked his disciples to teach the "Wan Zang Sword Sutra" in person! The rivers and lakes are shocked by it! Chu Huoluo, a female disciple of Lieyang Mansion, became Shen Zhenyi's apprentice by chance. As the master and apprentice broke the puzzle, the crisis was quietly approaching, and when the final conspiracy surfaced, all the reasons pointed to an ancient legend called "Zhanyue Feixian".

He stood at the pinnacle of the world. Surpassing all since birth in the art of the sword. But fate has left him crippled moments before reaching the apex. But the story continues and the legend will rise again.

In Edo period Japan (1603 to 1868), a strange new disease called the Redface Pox has begun to prey on the country's men. Within eighty years of the first outbreak, the male population has fallen to a quarter of the total female population. Women have taken on all the roles traditionally granted to men, even that of the Shogun. The men, precious providers of life, are carefully protected and the most beautiful of the men are sent to serve in the Shogun's Inner Chambers.

In the anime, Kuromi is traveling the world, searching for her missing older sister Romina. Throughout her journey, she gains companions, but also brushes up against evil organizations.