Chuuzenji-sensei Mononoke Kougiroku: Sensei ga Nazo wo Hodoite Shimau kara.

In Tokyo in 1948, student Kanna Kusakabe enters school expecting an ordinary life, only to become surrounded by rumors of ghosts, curses, and incidents that seem supernatural. In an abandoned preparation room filled with old books, she meets Japanese-language teacher Akihiko Chuuzenji, a gloomy man who knows a great deal about superstition while having little patience for believing it.

Whenever another strange event appears, Kanna is drawn into it and eventually turns to Chuuzenji for help. What others describe as spirits or monsters may conceal deception, fear, or ordinary human misunderstanding, and he refuses to accept a mystical answer when the truth can be dismantled logically. As the cases accumulate, Kanna gains an unwanted reputation as an expert on the occult while her irritable teacher remains the last person willing to admit that anything supernatural happened at all.