Ayame, the granddaughter of northern wolf yōkai tribe leader, searches for Koga, who is needed to unite the northern and eastern tribes, once proposing to marry her during childhood. Meanwhile, a mouth incarnation of Naraku is attacking everything in sight and Koga decides to take off with Kagome to protect her, only to run into an angry and jealous Ayame. It is explained how Koga once saved Ayame from the terror of the Birds of Paradise, while promising to marry her during the night of the lunar rainbow.