The Mystery Files of Detective Inaba No. 3

Nina Arimura is a high school student who assists at the Inaba Detective Bureau in her spare time. The rumor circulating at school is specific: a nearby mansion is home to a ghoul, and people who have gone inside have not come out. When Nina discovers that classmates are planning to enter, she follows them in—and shortly after, calls Detective Sogo Inaba for help. Inaba will have to investigate the abandoned mansion alone.