Hiromu Arakawa, award-winning manga creator of the best-selling smash hit Fullmetal Alchemist, draws readers into an intricate new web of magic, intrigue, and life-or-death stakes!

In a world where certain humans command mighty supernatural duos called Daemons, it is the birthright of "the children who sunder day and night"--twins Yuru and Asa--to rule over these powerful entities.

Separated from a young age and unaware of the truth of their birth, brother and sister must fight to make their way back to each other, claim their birthright, and save the world...

Ancient Daemons awaken to fight a new battle in an age-old war!!

Dera suddenly arrives at the manor, as if to interrupt Yuru's somber thoughts about Asa's past. Though a tense debate about the twins unfolds, it's Yuru who has the last word: a brash declaration to all hostiles! As he leaves the Kagemoris behind for Dera's secret lair, however, a vicious pair of Daemons lies in wait. Right and Left must take on a primal evil to keep their master alive!