arima souichirou
The male lead of the series, Arima Souichiro is a "perfect" human being... or is he? Troubled by his past and the blood that runs through his veins, he strives to make his foster parents proud by hiding behind an impenetrable mask...
The beginning of the series finds him to be a very popular guy, excelling in sports and academics. He is involved with the kendo club and the student council. Amidst all of the girls who seem to have fallen for him in high school, he is instead intrigued by Miyazawa Yukino, who he views to be the perfect girl. I guess like calls to like, as he is also harboring a different personality within. Although she barely notices him at first, he does whatever he can to gain her attention... including offering to lend her a Brahm's CD. Because of a particular incident at this time, he discovers Yukino's real self.. and, later, as their relationship develops, he vows along with her to become truer to themselves.
And, although it seems that he's released some of his former inhibitions, his past still continues to haunt him, holding him back from completely showing his real self to others, afraid of the hurt the exposure may bring. He is afraid and ashamed of his cruel past, although his friends reassure him that they like him for who he is, and that they are willing to protect him.
We learn a lot later that despite giving it his all to become a doctor to someday take over his adoptive father's hospital, he actually aspires to be a police detective.