Just before the new semester began, Misaki Fujioka dropped by her twin sister Mei Misaki in Yomiyama City. The sisters spent the remaining summer days exploring a sun‑baked town, stopping by a mall and an archery range. While wandering through Mei"s basement, she voiced her dread over the rumored cursed class she would soon join.
Seeking more fun, the twins headed to a nearby amusement park. Yet the calm of a languid summer afternoon quickly turned grim when Mei noticed a deathly hue on Misaki—an unmistakable sign that disaster was imminent.