Blade of the Immortal: Legend of the Sword Demon (Light Novel)

Rendered immortal by an infusion of mystical worms that can repair any wound, the masterless samurai Manji wanders the hillsides of feudal Japan, his quest to slay one thousand evil people to atone for his past sins. By his side is the young woman Rin, an orphan who seeks vengeance for the murders of her parents.