The series follows Seiichirō Kitano, a kind and naive boy with the heart of an angel, but the sinister looks of a devil. This paired with his horrible luck and awkward social skills causes many misunderstandings, leading people to assume that he is a delinquent and heroin addict, and (unbeknownst to himself) results in a career as the head thug, or "school guardian" at his new school.
They are known as special guidance counselors, but they are actually working for the Education Committee. They are known as the "Shadowy Seven" (and "Shadowy Six" after Shirataki's retirement).
Irie, the first of the seven guidance counselors, seen in chapter 7.
Kumagai, the most warrior-like of the seven.
Shirataki, the third special guidance counselor dispatched from the Education Committee to deal with Kitano.
Haruka Hishida, first seen in chapter 43.
The other three members of the seven/six were never introduced during the series.
Kitano's Parents
Ryuichiro Kitano (北野 隆一郎, Kitano Ryūichirō), his father, an ordinary office worker, first seen in chapter 21.
Midori Kitano (北野 みどり, Kitano Midori), his mother, first seen in chapter 21.
Ryoko's Parents
Heizo Koiso, Ryoko's father.
Mrs. Koiso, Ryoko's deceased mother.
The Halford Family
Papa Halford, an American with a Japanese wife and two children, who moved to Japan 20 years ago.
Mama Halford, introduced in chapter 66.
Leo Halford (レオ·ハルフォード, Reo Harufōdo), the half-Japanese first son of the Halford family.
Sana Halford (サナ·ハルフォード, Sana Harufodo), Leo's little sister.
Others
Kiyomi Kaburagi, president of the Photography Club at a high school near Hekikuu High.
Kikuchi, a member of the Photography Club.
Yamazaki, a member of the Photography Club
Noguchi, a member of the Photography Club
Chuji Asai, Midori's cousin, only seen 18 years ago in chapters 76 to 78.