Yorie Usami (Yasuko Sawaguchi), a teacher at Priory Girls' Academy, strictly follows the school's precepts. One day, Usami kills Tetsuya Abe (Kazuyuki Aijima), a free-spirited teacher and fakes the death as an accident. Furuhata is suspicious of the various things left in Abe's room and suspects Usami to be the culprit, but does not understand their motive, which may be hidden among the school's strict rules.
