Hatsuharu Sohma is 15 and the Ox of the Zodiac. Haru has something of a Dr. Jekyll and Mr. Hyde complex related to the Ox's personality. He is usually calm and placid as the White Haru, like the Ox is usually calm and placid, but can be goaded into "stampeding", the Black Haru, where he could be edgy, mean and slightly oversexed.

Unlike Kagura Sohma who is completely clueless when she transforms to her violent side, White Haru is conscious during his "black" transformation, but is unable to do anything about it. He just either apologizes or ignores the situation. He's somewhat an interesting character. Additionally, Haru has a rather bad sense of direction.

He has a bicycle but got lost somewhere in his travels. Haru likes to make fun of Kyo passively and wants to fight with him on a regular basis. This all started when he was little. He held a grudge against Yuki. People in his family always made fun of him about how the cow was stupid and let the rat used the him. This made him mad, so mad that he developed a black personality. He soon had forgiven Yuki Sohma after he knew him better.

Haru is mostly seen wearing rockish attire, like biker clothes. It's so sad. He only rides a bicycle because he's not old enough to ride a motorcycle.