At the start of the 21st century, in the Uchihama area during autumn, a tale unfolds. The popular Uchihama Academy is expanding rapidly and as a new school building is erected, the last General Club Festival is planned for the old building that is scheduled to close. The students promise to put their all into making this final cultural event a success. The renowned Astronomy Club, led by protagonist Sou Akiyama, boasts the most prominent names on campus. However, just before the festival on October 1, the club is approached by the student executive committee with a request to quell the unease among students caused by reports of ghost sightings, accidents, sleeping sickness, and other mysterious incidents in the old building. When a reticent transfer student named Yui Furukawa appears before Sou, the wheels of destiny start moving slowly but surely.