The day has come for Horoboros, a monster that Yuka saw as a child, to awaken from its long slumber! The key to appeasing the raging Horoboros lies in a mysterious word recorded in an ancient document. Yuka sets out to decipher this writing, but Kaburagi's dark power is reaching out to Horoboros...!

While investigating the curious case of a vanishing monster. Haruki meets Kaori, a mysterious woman glaring at an old ferris wheel. Meanwhile, people are going missing from the town one after another.