Satoshi Miwa

"The student body president and a third year student. Many girls are interested in him, but he is only interested in Meiko, and tries to get her to like him in place of Na-chan. His crude sense of humor however, do not sit well with Meiko, who believes him to be irresponsible and a playboy. They do go out for a time, but Meiko is unable to overcome her feelings for Na-chan. After Satoshi tries several times to make her forget him, following the Hiroshima arc he sees that he has no chance to win her over and stops his romantic pursuit of Meiko, staying friends with her instead.

Satoshi is the first person to notice Yuu's interest in architecture, and his initially unusual behavior towards Yuu arouse Yuu and Miki's suspicions that he is gay and has a crush on him, which he uses to his advantage. Satoshi and Yuu eventually come to an understanding however, and Satoshi helps Yuu try to uncover the truth of who his actual biological father may be, as he suspects that his father Yoshimitsu is a potential candidate. It is revealed however, that Yoshimitsu is not Yuu's true father, but Satoshi and Yuu stay best friends after this."

(Source: Wikipedia)