Hayasaka Kaori is a delinquent at Midorigaoka Academy in Class 2-1 who became one of the first members of the Public Morals Club along with his classmate Mafuyu Kurosaki.

Hayasaka is a delinquent and a classmate of Mafuyu. After a series of events Mafuyu declares Hayasaka her best friend, although he's actually deathly afraid of her at first because of the dark aura she emanates during class. Later he and Mafuyu are forcefully recruited into the disciplinary club by Takaomi.  

Mafuyu is the no-nonsense, take-charge and hard-hitting leader of her high school gang. But when she gets expelled for being a delinquent, her mother, fed up with her daughter's wayward ways, sends Mafuyu to an isolated school far off in the country.
 
Determined to make the best of the situation and make her mother proud, Mafuyu decides to turn over a new, feminine, well-behaved leaf. But her fighting spirit can't be kept down, and the night before school starts she finds herself defending some guy who's getting beaten up. One slip wouldn't have been a problem, except the guy is…her teacher?! How can Mafuyu learn to be a good girl if her teacher won't let her forget her wicked past?
 
(Source: Viz Media)
 
Note: Chapter count includes the one-shot “Omae Watashi no Koto Suki daro” and 1 extra chapter.

Kaori Hayasaka