Transfer student Kouichi Sakakibara returns to Yomiyama North Junior High's class 3-3 after missing the first month of school due to illness. He is strangely drawn to Mei Misaki, a shy girl with an eyepatch whom he met in the hospital during his absence, among his new classmates. However, none of his classmates are aware of her existence, and they caution him against becoming acquainted with things that do not exist. Despite their warnings, Kouichi meets Mei, soon discovering the deadly reality behind his friends' fears.