|Height and Weight||174cm, 64kg|
|Class and Year||2-F|
|Manga||Volume 1 Chapter 3|
Kawahara is a perverted masochist that is addicted to abuse from girls such as Chitose Karasuyama. According to Kenji Kazama in episode 1, he is Kenj's only friend who has changed as he became a masochist.
Apparently, Kawahara doesn't like being called Vice President and wants his friends to call him "Acchan". In addition, he claims that he is the only one that haven't become a delinquent.
Kawahara lost the Student Body election to become president, so he decided to become vice-president instead so that he could help his old school in some way.
In the past, the Kazama Party was at the top department store's roof when a fire suddenly started downstairs. Shaun Konekone suddenly appeared with a rope which allowed them to climb safely down from the roof thus saving their lives. in volume 9 it is revealed in a sort of flashback from the two students who encountered Kenji Kazama in volume 1 chapter 1 that he has his own little gang of masochists whom assist him in getting information from his rivals mainly the gangs in Fujouh High and his main rival
- The name Ataru means "middle" (中).
- Ataru's surname Kawahara means "river, stream" (河) (kawa) and "field, plain" (原) (hara).