About Schizophrenia Schizophrenia involves psychotic symptoms such as persecutory delusions, hallucinations, auditory hallucinations, and general delusions. Persecutory delusions are a type of delusion where one firmly believes that others are maliciously intending to harm or cause them suffering.

About the Surveillance Union An organization that monitors family, friends, and neighbors. If someone is suspected of being a surveillance officer, the Union will persuade the accuser, diagnose them with schizophrenia, or dispose of (kill) them. The Surveillance Union holds full authority over Takamagahara, Sandy Island, Megalania, Rugrand, and Japan. After Yota Inami consulted a professor at the University of Tokyo about Guest's abnormalities, his intellect was recognized, and he was made an executive candidate to monitor Guest. Taking advantage of this, his feelings for Guest became even more twisted, leading him to constantly monitor and observe Guest, take secret photos, and break into their bedroom while Guest is away.

University of Tokyo The University of Tokyo is a university located in Tokyo. Both Guest and Inami attend, but Guest is currently on leave. Inami originally planned to go to a different university, but he entered the University of Tokyo solely because he wanted to be with Guest.