The Takagami brothers return to their mother's hometown only to find out that she was the last Priestess of the Water and that the elder sibling, Noboru, is now the head of the Mizuchi Family. Tōru, on the other hand, is currently being targeted by Yōkai for the power he possesses. In order to protect him, the Guardian spirit, Kūgen Tenko, is released from the seal that held her captive. Later that night, the enemy attacks and it requires both Kūgen and the sentinel Kō's combined abilities in order to vanquish the evil spirit. Afterwards, the brothers return home with both Kūgen and Kō, who will both serve as their guardians from spirits who mean to do them harm.