The Head Girl Kanna Nozaki’s Sex Crime Archive ~Gather Clues By Sex~

The head girl in the Yari-Man Academy Kanna Nozaki is keeping
an eye on students’ morals as always. One day, a case of panties
theft happens in this school, so Kanna set off for investigation.

Basically, her means of investigation are intimidation and honey trap.
She finally reaches the perpetrator after all. What is the motive of the crime…?