Seikichi Kuroda
About
Kuroda desperately tries to reserve a leftovers of his dignity by acting like a guardian before Ogisu and his sempai. Also he has one-sided crush on Ryoko.
Ooshita and Tokiyama are his two lackeys/friends. Both of them have rarely been referred to by their actual names. Koide, the class president's assistant calls it a "miracle" that he was able to obtain their full names. As the story progresses, they realize Kuroda's weakness (and strengths, rarely good, though), but they kept on being loyal to him.
Another piece of trivia from the author himself, Kuroda serves as a pivotal character at the very start of the series, when the author experienced a writer's block.
(Source: Wikipedia)