Kumiko (known by her students as 'Yankumi') becomes a teacher at an all-boys private high school called Shirokin High. Her class is full of delinquents, but she tries her hardest to teach them not just about academics, but about lessons of life, much like any 'dedicated teacher' story. Though she's forced to keep her family a secret from the public, her Yakuza upbringing gives her the strength and the experience to reach out to her students, while also providing comedic relief.
Please note this wiki will only provide information for what happens in the anime and manga. Please look somewhere else for information on the live-action series.