Mai and Ai Amatsu, the popular "Twin Dolls" of Tenjin Academy, are the heirs to a sacred priestess tradition. When the demon prince Hakumouki exploits a student's jealousy to launch a brutal attack, the twins are captured and subjected to demonic torment. However, by unleashing the power of the Dance of Celestial Raiment, they manage to defeat the invaders, though they are warned that a far greater evil is soon to be reborn.
As the Tenjin Archery Tournament approaches, Ai and Mai Amatsu continue their training to protect the mischievous descendant of Tenjin, Onimaro. During the festival's purification rituals, the demon Sekimouki launches a surprise attack, sealing the twins' powers and attempting to abduct Onimaro. Despite the onslaught, Ai and Mai synchronize their spirits to unleash the powerful Thunder Dance, repelling the demon beast and reaffirming their duty as Tenjin Watchers.