Oshioki: Gakuen Reijou Kousei Keikaku

My name is Shimohei Joutarou. There is a reason that I'm here, at my new place of work, despite the fact that the school year hasn't started.

On that first day, I almost immediately came across Mitsuki's and Minami's secret. I then heard about Mahiru, younger sister of Classics teacher Kuji ....