Blade of the Immortal

Blade of the Immortal (無限の住人, Mugen no Jūnin, lit. The Inhabitant of Infinity) is a Japanese manga series by Hiroaki Samura. The series is set in Japan during the mid-Tokugawa Shogunate period and follows the cursed samurai Manji, who has to kill 1000 evil men in order to regain his mortality. The manga was originally published in Afternoon from June 25, 1993 – December 25, 2012. A 2008 anime adaption was produced Bee Train and Production I.G. Also in 2008, the novel Blade of the Immortal: Legend of the Sword Demon was released in the United States by Dark Horse Comics.

Plot
Manji is an amoral swordsman, who has been cursed with eternal life. He has grown tired of living with all the death he has created. He has no skills other than those of killing, thus he forms a plan to regain his mortality: he shall kill one hundred evil men for each good one he has killed. The old witch who afflicted Manji with immortality agrees to Manji's proposition and Manji is set on his path to kill one thousand evil men. On his journey he meets a young girl, Rin, who has her own vengeance to seek against the sword school whose members slaughtered Rin's family. Rin and Manji journey together, each hoping to find some kind of peace. In their way are many varied enemies. Rin and Manji are almost constantly under attack and must learn to live their lives, avoiding being consumed by revenge.