Yuki Kurokawa (黒川 雪, Kurokawa Yuki) is a member of the school tennis club with a dark past. She is friends with Utsumi Seiji.
Yuki has black hair, which extends just past her shoulders. On the right side of her face her fridge is parted, brushing towards and covering the left side. Her ears are mostly covered by her hair, and she has dark-colored eyes.
Yuki is quite solitary, due to a horrible incident which led to her changing schools. She is, however, caring towards those she trusts, and is willing to give advice to those who are suffering through relationship issues.The pain she had gained before the start of the series rendered her unable to love again. However, she does gradually learn to warm up to people due to the maturing Seiji, whom she still considers a friend, much to his dismay.
Yuki belongs to a rich family from northern Japan. Before moving into Seiji's school, Yuki had a boyfriend, Toru. Toru and Yuki were extremely close, and were often seen by their friends as one person because they were so inseperable. At one point, Toru talked Yuki into having sex with him, which led her to utter humiliation when she found out having sex with her was part of a bet and was videotaped, and the video was circulated throughout her school. Deeply hurt by Toru's sudden betrayal, she cut off all ties with him and moved away from her hometown. Toru appears to have been looking for her ever since.
To date, Seiji and Yuki's family, as well as -obviously- Yuki herself, and the people in Yuki's old school (as is blatantly evident given the premise, since the video circulated throughout the school, or class) know about the event.
Yuki is introduced as a member of the tennis club, who one day begins encouraging Seiji to confess his feelings to her captain, Shou. Though successful, things go terribly wrong when Shou is discovered to have chosen to be with someone else, who she had liked for a long time.As the story progresses, the relationship between Seiji and Yuki becomes more complicated, and the two eventually begin dating, however, the scars Yuki gained end up making things go wrong between them, and soon cause a break up.
When Seiji and Shou begin dating each other, Yuki tries her best to hide her still lingering feelings, which mainly began after Seiji asked for her to become his girlfriend. This is because Yuki wants what is best for both Seiji and Shou, the latter who she continues to respect as a 'senpai'.
Sometime later, Yuki encounters Rico, the younger sister of her ex-boyfriend. Recognizing each other, Yuki dashes off in tears, leaving Seiji (who had unknowingly brought a person from Yuki's past to her) confused.
Due to this encounter, Toru is informed of Yuki's whereabouts, and begins persistantly trying to get her to return to him. Such acts lead to Yuki being worn out everyday, much to the concern of Seiji. Over time, Seiji begins to realize that he cannot forget Yuki and chooses to break up with Shou; a fact which horrifies Yuki.
After much talking through cell phones, Yuki eventually agrees to meet up in person with Toru, in an abandoned building which they used to play at when they were young. Out of concern, Seiji gathers a search party and eventually locates her, thus rescuing 'the love of his life' from Toru.
With things settled down, Yuki's life returns to normal, until her father comes home one day and forces her to leave school and possibly move to an all girls school, since her kidnap led to much shame upon the family name.
However, being unwilling to let Yuki go, and with the help of Yuki's mother, Seiji manages to come get her, and the two later walk along a beach. It is there that Yuki states, "As long as I'm together with you, that will be a good ending."
The two embraced, and ended up going to Seiji's house. With the support of the Shimazu family, she and Seiji went to persuade Yuki's parents, and were granted permission to 'do as they like'. Therefore, Yuki was allowed to return to school.
Afterwards, the pair focused more on studying, and although they went to a separate Campus, their relationship still continued.
On their 26th spring, when work had finally calmed down, they got married.
Yuki is now a doctor, working even after hours for the sake of her patients (resulting in much stress). Together with Seiji, they have a son named 'Hikaru'.
After Seiji's photo exhibit is closed, Yuki arrives with their son, and apologizes for being late, and saying that she wanted to see their old friends who had come. The three soon walk over to the only photograph that made it in, and that was the photo of when Hikaru was born.