Hoshino, Katsura

"After a savage battle, Allen and the Millennium Earl, leader of the akuma, confront each other--not as themselves, but as mysterious entities that came into being as seeming twin brothers during an even more mysterious episode in the Earl's past. Nea, the twin inhabiting Allen, has a mission: to destroy Mana, the one inhabiting the Earl. But then some of Allen's erstwhile allies in the battle against the akuma show up at exactly the wrong moment--for them!"--Back cover.

Allen Walker travels a dystopic nineteenth-century world with two companions in search of a demon-fighting substance called akuma, while attempting to suppress his demonic alter ego, the Fourteenth.

Allen Walker must traverse the Earth in the nineteenth century in order to find Innocence, a substance of extraordinary spiritual virtue which the ancients used to battle the akuma demons, before the Noahic Flood destroyed the world. Now, the Millennium Earl is rising again, and Allen has encountered the mysterious Cardinal, whose interest in Allen is unclear.

Allen Walker, a fifteen-year-old boy who roams the earth in search of Innocence, the mysterious substance used to create weapons to fight off demons, is washed away to unknown parts of the world after The Great Flood.

In a fictional nineteenth-century England, Allen is an Exorcist seeking "Innocence," a substance that can kill akuma demons. Now he is questioning his mission because his left eye is injured leaving him unable to detect akuma. Still he is sent to seek his master, Cross, to discover why the akuma are targeting leaders of the Black Ministry.

When Lenalee sets out to confront a Level 4 Akuma that's out to kill Komui, the Level 4 goes against the efforts of Lavi and Kanda and pursues its mission. Meanwhile, Allen is left to hold the line and finds it too much on his own.

As Krory becomes trapped in a seemingly hopeless situation, his comrades continue to traverse the Ark and encounter Tyki Mikk. As Tyki and Allen work out a truce, Lavi suspects that the Innocence is far more powerful than anyone can understand.

The Noah aid Lenalee, Lavi, and the others in their fight against the Millennium Earl's forces, but the agents of the Black Order refuse to give in, realizing that this may be the last stand of the Exorcists.

Fifteen-year-old exorcist Allen continues his mission to find Innocence to battle the deathly demons that plague his world. He uses the Innocence in his disfigured left hand, his ability to see into people's souls, and his connections with other exorcists to lead the battle against the Millennium Earl out to destroy mankind.