Under the threat of being disowned, Mafuyu Kurosaki—an ex-delinquent with a strong sense of justice, exceptional fighting skills, and a very dense head—must start a new life as a proper citizen and student at Midorigaoka Academy. In addition to adjusting to a new school, Mafuyu must also get used to living alone, as the dorms are full. As a result, she begins a new chapter in her life with limited funds, the inability to even make a cup of instant noodles, and a big dream of becoming "an ultra-shiny female high school student." This dream proves difficult to achieve, as Mafuyu's sense of style is uncouth, and trouble seems to find her regardless of how hard she tries to avoid it. Her path toward this goal becomes even more challenging due to Takaomi Saeki, her unordinary homeroom teacher with barely legal teaching methods, and her delinquent classmate Kaori Hayasaka, who becomes her first new friend. Oresama Teacher follows Mafuyu's adventure filled with hilarious situations, ridiculous misunderstandings, and exciting action sequences, all while she continues to try to become a normal feminine girl.