Personality and Appearance

Yahiro's Smile
Yahiro is a carfree young man with a sinister side. Yahiro is kind and gentle but appears to be heartless and deceptive. This is only, however, his only way of protecting Akira, whom he loves. He has pink, almost shoulder length hair and has dark brown eyes. Like other male characters, he has a slender build, a little shorter than Kei and Ryuu, but taller than Jun .
Background
Yahiro attends Kokusen Academy , another high school, but it is revealed that he originally studied in Hakusenkan, only to be expelled by Tadashi's mother. He is the heir to the Saiga Financial Group, a group that is even higher in status than the Takishima Group. When he was young, Yahiro had no friends, for the most part because his attitude prevented him from making anyone smile or laugh and made them cry instead. He chose not to become friends with anyone until he met Sakura; at first, he had rejected her offer to become friends with her, but complied after they went through a lot of trouble to save the rabbit they were trying to bring back to its home in the mountains. He is often seen, both in anime and manga, with Sakura, arranging parties and events. Yahiro often helps with the group's problems, seen in the time when Hikari was stuck in Aoi's villa, his helicopter was used to rescue her.
History
Yahiro has harboured a crush on Akira Toudou since childhood and is very protective of her, willing to use whatever means necessary to protect her, even if she hates him for it. It is this protective nature that made him drive away Akira's only friend, Sayo, after he overheard her saying how she never liked Akira and was only her friend because Akira was rich and she enjoyed all the privileges and status that came with the friendship. Akira had believed that Yahiro had been jealous of her relationship with the "poor" kid she was playing with and never forgave Yahiro for ending her friendship with Sayo. He never told Akira the truth and has no intention of telling her. His hatred of "poor" people comes largely from this incident, which made him believe the poor exploit the rich. A similar event happened when Akira becomes friends with Yui. It is this event which led them to talk to each other once more. He eventually gives up his feelings for Akira, telling Tadashi that if he ever makes Akira cry, he will never forgive him.
Because he still cares for Akira, Yahiro is unable to reciprocate Megumi's feelings for him, but comes to see her as an important person to him and encourages her to sing. At the end of the anime, Yahiro seems to become attracted to Megumi Yamamoto, when he attemps to kiss her, but is interrupted by Tadashi, causing Yahiro to yell, saying, "Aren't you wary of the atmosphere!". In the manga, they're closer than they are seen in the anime. He has hurt and rejected Megumi far more many times, and it was not really clear if his feeling were as strong as hers. But he constantly helped her saying 'I want to do it' like when she needed voice lessons and he also pretended to be her boyfriend in front of Megumi's mother.
Since he is born in the upper-class of society, he is good friends with Kei as he is with Akira since childhood, a relationship almost the same with Akira, Kei and Hikari. He holds the distinction of having beaten Kei once during their childhood in a game of tag which Kei lost because Yahiro had locked the door to the roof to prevent Kei from winning. Yahiro's first encounter in the series with Kei is after he helps with Hikari's measurements during his birthday party, in which Kei asked Hikari to accompany him. He later starts an absurd game in his party in which anyone who can catch Hikari get any prize they want. They meet later at the rooftop where Yahiro is waiting with Hikari. He attempt to kiss her in front of Kei but is stopped. Later, he asks him how Akira is doing. Hikari, still oblivious of the situation wonders to herself what kind of situation it is.