Yomiyama is his deceased mother's childhood home, and, while his father is abroad in India, Koichi is temporarily staying there alongside his grandmother and aunt, Reiko, who is also Class 3-3's homeroom teacher.

When a student is trying to stop him from talking with Mei, she suffers a fatal freak accident in which her neck becomes stabbed by the sharp end of an umbrella.

Chibiki tells them the truth about the accidents, which are actually a curse connected to Misaki Yomiyama, a student of Class 3-3 who died 26 years ago.

Due to the extra body count, another student has to offer themselves to be excluded for the entire year; if the rule is broken, nature is compelled to "delete" the class members one by one.

The tape, recorded by a Class 3-3 student from the year 1983, is a method of how to temporarily end the curse: by killing the extra person during the school trip held in August.

14 years later, Koichi visits Yomiyama North to hand the tape to a student of Class 3-3, whose classroom teacher is revealed to be Chibiki.