Nadeko spent the evening at the Araragi residence after Koyomi mistakes her for running away from home and takes her back to his place. The next morning, she talks to Koyomi's younger sister Tsukihi, a friend from back in grade school.

Koyomi returned from the time warp with Shinobu. From North Shirahebi Shrine, he headed home together with Mayoi Hachikuji and returned her backpack to her. However, right afterwards, the two of them are assaulted by a mysterious “Darkness.”

Kaiki, deciding to accept Hitagi's work request, visits the town where Koyomi and his friends live. He starts to do research on Nadeko Sengoku, the junior high school girl turned god of North Shirahebi Shrine, who is the current target of deceit.