After years of separation, high schooler Shoma reunites with his childhood friend Atsushi at a secluded festival. However, Atsushi is missing, and in his place stands Shiori, a girl with her own quest. Encouraged by Kanna, the festival organizer, Shoma decides to stay and assist with the event. As they delve into their tasks, Shoma and Shiori find themselves entangled in the town's mysterious occurrences.