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.

Rin announced that she will go meet with her father's friend Souri, the painter, in her journey for revenge. Souri cannot lend her a hand, but instead gives her funds. Rin, now with a full wallet and no leads, finds her father's sword at the blacksmith from which it was supposedly stolen. However, its wielder is a swordsman of the Ittou-ryu, 'Taito Magatsu.'

A prostitute approaches Manji as he waits for Rin. Though Manji sees through the prostitutes ruse, he accepts her invitiation. But this woman, 'Makie Otonotachibana', seem to weak to be a warrior of the Ittou-ryu as she claims. After sparing Makie's life, she appears before Manji again with different eyes and hair.

After seeing Kagehisa, Rin becomes weak at the knees. Lost in thought over her circumstances, Rin and her guard Manji are approached by a Buddhist monk. The monk is 'Eiku Shizuma' of the Ittou-ryu. He fights with Manji but is swiftly cut down. However, despite the lethal blow, Shizuma stands back up, his wound mending itself completely. Shizuma possesses an 'immortal' body, just like Manji.

Discussions of the task of naming the instructor at the Ittou-ryu school, allotted them by the shogunate, have begun. They will make the Ittou-ryu's sword known to the world. Taito Magatsu vows to make that a reality, but decides to leave from Kagehisa Anotsu's side. At the same time, Ittou-ryu leaders start to be targeted. The tip of that blade is also pointed at Magatsu.

Rin was told of Kagehisa's whereabouts by Giichi, and now her and Manji are suspected of indiscriminate murder. Suspected criminals cannot pass the checkpoint. But thanks to a maid who was acquaintance of Rin's, she has a countermeasure. She heads alone to a village that can help her slip through the checkpoint.

Having become traveling partners for the sake of their goals, Manji and Magatsu are assaulted by a group of bald men. Manji, groaning in pain, is approached from behind by Shira, who then lops off Manji's arm. Shira had reconstructed his body, and desired a rematch with Manji. But now Magatsu, whose important woman was killed by Shira, stands in his path.

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.

The Ittou-ryu had its members slaughtered by the shogunate. Kagehisa gathers the remaining members of Ittou-ryu in secrecy, and plots revenge against the shogunate. Manji is invited to the Mugai-ryu by Giichi, but he refuses, and they clash swords. Giichi's weapon breaks, so a truce is called. Manji decides to go meet the head of the Mugai-ryu, Habaki.

After his failure at Edo Castle, Habaki is dismissed as head clerk. But still, in order to annihilate the Ittou-ryu, he heads up the Rokki-dan in hopes of subjugation. However, the new head clerk, Ugen, decides that Ittou-ryu, having left Edo, is now in the clear. Furthermore, to ensure he abides by the agreement, Habaki's wife and children are taken hostage.

The Ittour-ryu are pursued by the Rokki-dan, lead by Habaki. Upon hearing this, Run and Manji decide to pursue as well. Even with all these people leaving Edo to chase the Ittou-ryu, the four leasers appointed by Kagehisa Anotsu are nowhere to be found. Then, in the wee hours of the morning, Kagehisa and the other three stand at the Ootemon in front of Edo Castle.

Arashino, Hasshuu, and Murasaki of the Rokki-dan act as the vanguard in the clash with the Ittou-ryu. The crucial Abayama manages to escape with the help of his followers. But then he hast to confront Giichi and Hyakurin, who pursued Abayama to assist Habaki.

The lives of those gathered fizzle out one after another. Those remaining are battered and bruised. Yet still they take up their swords, and slam their convictions against one another. The last one standing... And the revenge that was fulfilled... The curtain now closes on the tale of the man with an eternal life, and of those people whose finite lives were a blaze of passion.