Cloak of night
(Book)

"After the devastating Ceremony of Two Hundred Hearts, Sora, Daemon, Fairy, and Broomstick are truly alone in the fight to save their kingdom. Empress Aki is missing, and everyone else who could help them is a prisoner to Prince Gin's mind control. At least Sora understands what they're up against. Or so she believes, until she overhears Gin bargaining with the god of war for immortality and learns that ryuu magic may be a more insidious danger than she realized. Suddenly, the stakes are higher and even more personal for Sora-not only must she stop a seemingly indestructible Prince Gin, but she must also unravel the secrets of ryuu magic before it is too late for nearly everyone she loves. Sora Daemon, Fairy, and Broomstick face dangerous obstacles at every turn, but the greatest challenge may be discovering who they truly are and what, if anything, they are capable of."--Dust jacket.