Because there are rumors about unconfirmed creatures and supernatural phenomena circulating in the Wind Festival, Kotaro asks Chisato Akane, the head of the Supernatural Research Society, for help, and then begins an investigation involving students Kotaro knows. For Kotaro, it was originally just a little adventurous. As long as he can spend time with his lively friends, it's enough. But Kotaro hasn't realized that he will explore the "truth" that no one knows.