The Edo period. Daughter of a martial arts dojo, Rin embarks on a journey to take revenge for her slain parents. For her bodyguard on the journey, she has chosen the immortal man Manji, nicknamed the Slayer of Hundreds. Her target is the head of the Ittou-ryu, Kagehisa Anotsu, the man she hates. The adventure of the man who never dies and the girl who's sworn to live for revenge unfolds.

Manji and Rin involve the four known as Mugai-ryu, who hold information on Kagehisa, in order to assassinate him. Lying in wait on the road that leads out of Edo, based on information only known to Rin, she and Shira close in on Kagehisa as he tries to flee from the others.

Having left for Kaga in pursuit of Kagehisa, a collapsed Rin is rescued by the very same Kagehisa. Then, having to cooperate with Kagehisa who is pursued by the Shingoto-ryu, Rin starts to see Kagehisa, her enemy, as a human being.