中禅寺先生物怪講義録 先生が謎を解いてしまうから。

In 1948 Tokyo, just right after the war, Kanna Kusakabe had just become a second-year at a high school when she meets the new language teacher, Akihiko Chuzenji. Mysterious supernatural things keep happening around Kanna. Once again today, Kanna is going to open the doors to the library prep room to seek help from the surly Chuzenji-sensei who is waiting inside.