The root of all evil lies in Chuunibyouji (eighth-grader syndrome). Every delusion, crime, and psychic phenomenon in this world began with chuunibyou-sickness. The dark energy of chuunibyou-sickness, causes the craziest incidents.

One night, Sakura witnesses a murder through the blinds of her apartment. However, she is unable to identify the killer because he’s masked. The more Sakura thinks about it, she begins to suspect her older sister’s boyfriend as the murderer!