Kaoru is an androgynous beauty. She's one year older than Nanako, but she's in the same class as her because a mysterious disease prevented her from attending school for a year. Kaoru is a real leader, in fact, besides being the "class-leader", she's also the captain of the school basketball team. She has a noble and generous heart, and can't bear any form of injustice or abuse of power.

The name everybody calls her, "Kaoru-no-kimi" (Prince Kaoru), comes from Kaoru Udaisho, a noble character from the ancient Japanese tale Genji Monogatari, a character famous for his beauty and the divine fragrance coming from his body.

Kaoru is well-known for her intense vitality and her incredible love for life; she's probably Saint Just's closest friend, she deeply cares for her and often gets mad at Rei's neglect for her health. Kaoru's heart still belongs to a person who is very close to Nanako, a very deep relationship she decided to end....