All his life, Riku Tachibana has been raised by his grandfather. For some reason, the old man has always been fond of strange hand gestures, and they've rubbed off on Riku, who performs them almost subconsciously, to his classmates' great amusement. One day, however, it suddenly becomes clear to Riku what his grandfather has been surreptitiously teaching him. And the teachings could mean the difference between life and death for Riku.—Manga

Tachibana Riku is an orphan who lives with his adoptive grandfather. Other than school and homework, Riku has to put up with lessons from his grandfather, teaching him seemingly meaningless hand signals and signs; meaningless, that is, until Riku is violently introduced to the world of 'shikigamis', fighting beasts with human owners. After witnessing his grandfather defend against a shikigami assault on their home shrine, Riku obtains his own Drive device to summon his own shikigami, Kogenta, and it turns out the hand signals give the shikigamis special powers. With his newly obtained powers, and a shikigami as a companion and friend, what adventures await Tachibana Riku? Do his powers have any relation to his parents' disappearance?—Anime-Planet

Onmyou Taisenki literally translates to 'The Chronicles of the Great Yin-Yang War'. The series makes clear references to I Ching and to the Taoist theory of the five elements: Wood (ki), Metal (kin), Earth (chi), Fire (hi) and Water (mizu). Various Taoist elements are incorporated within the story: the existence of the four Kimon (lit. 'Demoniac Portals'), the use of cards that act as the Onmyoudou's amulets (toujinfu), the use of trigrams to represent direction when the Drive is swung, the emphasis on the balance of the sekki (the 24 seasons), and the character Nazuna, who is a Taoist maiden. Also, the show itself can be split into four seasons (13 episodes each), each with its distinct story, purpose, and goals.—Milton W.