Sensei no Koto ga Suki Nan Desu妹、やめます。; 老师我一直好喜欢你; Sensei no Koto ga Suki nan desu

Sayumi has been in love with her neighbour Sou-chan for years. He is by seven years her senior, so she decided to confess to him after entering high school. But what will she do when he suddenly becomes her homeroom teacher?