"By: Agnes Yoshida/Stephanie Sheh (starting from volume 4)
The Demon Hordes threaten the peace of Dusis and only the Dragon Lord Lykouleon and his Dragon Tribe can stop them.
With their forces weak and their magic dwindling, they will need the help of the magical elemental dragon swords to protect their kingdom. Each of these powerful swords chooses its own master -- the Dragon of Fire has chosen the Yokai (humanoid demon) Rath as its master, the Dragon of Earth has chosen the human thief Thatz, and the Dragon of Water has chosen an elf, Rune. These disparate soldiers, all pulled into a war that is not their own, are now charged to defend the realm against the encroaching demon forces.
But most everything in Dusis is not as it seems. A vast tapestry of quirky characters, each with its own agenda, make the already daunting task of defending the Dragon Realm downright near impossible. And if the Dragon Knights are to defeat the Demon Army, they will first have to defeat their own personal demons, which may be far more formidable than any monster in the whole world ... " from tokyopop.com