The greedy samurai lord Daigo Kagemitsu's land is dying, and he would do anything for power, even renounce Buddha and make a pact with demons. His prayers are answered by 12 demons who grant him the power he desires by aiding his prefecture's growth, but at a price. When Kagemitsu's first son is born, the boy has no limbs, no nose, no eyes, no ears, nor even skin—yet still, he lives. This child is disposed of in a river and forgotten. But as luck would have it, he is saved by a medicine man who provides him with prosthetics and weapons, allowing for him to survive and fend for himself. The boy lives and grows, and although he cannot see, hear, or feel anything, he must defeat the demons that took him as sacrifice. With the death of each one, he regains a part of himself that is rightfully his. For many years he wanders alone, until one day an orphan boy, Dororo, befriends him. The unlikely pair of castaways now fight for their survival and humanity in an unforgiving, demon-infested world.

Manji is an infamous swordsman in feudal Japan who is known as the "Hundred Man Killer," as he has killed one hundred innocent men. However, there is something far more frightening than his ominous reputation: the fact that he is immortal. This is the handiwork of eight-hundred-year-old nun Yaobikuni, who placed bloodworms capable of healing almost any wound in Manji's body. To atone for his crimes, Manji resolves to kill one thousand evil men. Yaobikuni agrees to this proposal, saying that if he succeeds, she will undo his curse of immortality. Soon after this promise, Manji meets Rin Asano, a 16-year-old girl who requests Manji's assistance in killing those who slaughtered her parents. Initially reluctant, Manji refuses Rin's desperate plea. However, owing to her evident lack of strength, Manji changes his mind and agrees to protect Rin for four years. With this partnership set in stone, the two embark on a perilous journey of bloodshed, vengeance, and redemption, each to fulfill their own life's cause.

A Hakuouki: Otogisoushi special episode that aired between episode 11 and episode 12, it was not included in the normal episode count of the main show. It had a TV and web release on the same day and is included on the DVD and BD release.

A village in danger, a mysterious child, warring daimyo, and the greatest ronin never known all clash in a Japan of magic and mechs. Learn the story of the first African samurai.