One day, high school student Miko Yotsuya suddenly gains the terrifying ability to see grotesque and dangerous spirits that no one else can perceive. Surrounded by these horrifying entities at all times, she adopts a desperate survival strategy: to pretend they do not exist. No matter what she witnesses, even when her cheerful and food-loving best friend Hana Yurikawa is possessed or when their classmate Yuria, a self-proclaimed spiritualist who can only see weak spirits, grows suspicious of her, Miko forces herself to show no reaction.

The story is set in a seemingly ordinary Japanese town and follows Miko as she navigates the daily challenges of school life while under constant supernatural siege. Her resolve is pushed to its limit with the arrival of a substitute teacher, Zen Tono, who takes over for their homeroom teacher on maternity leave. Miko observes that Tono is followed by a massive and ominous female spirit, and his presence seems to have a strange, negative effect on Hana, who eventually collapses. Determined to save her friend from a threat she can no longer ignore, Miko reluctantly teams up with Yuria and the diligent student council president Akio Gondo to investigate Tono's mysterious past. Their search leads them to uncover a shocking truth about the substitute teacher and the powerful spirit that clings to him, forcing Miko to confront a terror that she cannot simply pretend to overlook.