Chikane and Himeko share the same birthday and it's rapidly approaching. On the day of their birthday, the Orochi are awakened and at first Sōma attacks Himeko who is the Solar Priestess. Eventually, he comes to his senses and is able to fight back against another one of the Orochi, the Second Neck, Sister Miyako. Chikane and Himeko share a kiss.

The story of the Orochi and the Priestesses is revealed to the unsuspecting Solar and Lunar Priestesses. Later, Himeko contemplates on leaving the town, but first a fight ensues between the Priestesses and the Third Neck of the Orochi, Girochi. Finally, before things get too out of hand, Sōma comes to the Priestesses aide.

While Sōma and Himeko are on their date, it begins to rain and they take shelter in an abandoned warehouse. Meanwhile, Chikane has an encounter with the Second Neck of the Orochi who also begins playing with Chikane's feelings for Himeko. Later, the Third, Fourth, Fifth and Sixth Necks of the Orochi all attack Sōma while on his date with Himeko. After the fight, Sōma kisses Himeko.

After Himeko strikes Chikane's chest with her sword, they share a tender moment which ultimately reveals the unpleasant past the two Priestesses have shared in their past lives and how Chikane only pretended to want to kill her as to pay the cost this time around. The Orochi are finally defeated and everything goes back to normal, but at a price the two Priestesses were not ready to accept. At the end of the credits, a special ending is revealed which shows Himeko and Chikane being reunited.