Ukyo Kuonji is one of the Ranma's fiancées, and an okonomiyaki chef.
Ukyo is Ranma's childhood friend. Since they were kids, she and Ranma have played a game in which they both play and fight every day. In the end, Ranma defeats her every day.
At the time, her father proposed Genma to get Ukyo engage to Ranma. Genma gives Ranma a decision: Ukyo or okonomiyaki. Ranma chooses the latter, and Genma walks away with her cart, leaving Ukyo angry at that time. She becomes targeted by other girls, who mock her for not being feminine enough to keep Ranma. As a result, Ukyo gives up on being a girl and start acting like a boy and trains hard to get revenge on Ranma.
10 years later, Ranma meets her again, but still unaware that she is a girl. In the duel between them, Ranma is finally aware that Ukyo is a girl, and trouble begins between the two of them. As Ukyo was about to finish him off, Ranma calls her "cute". This angers Akane Tendo, who is engaged to Ranma. Afterwards, Ukyo forgives him and re-establishes their engagement the next day.
Ukyo also fends off another childhood friend of hers named Tsubasa Kurenai, who also follows her around, and challenges Ranma in a duel for Ukyo's affections. The cause of Tsubasa's challenging of Ranma was due to a picture sent to him with Ukyo and Ranma, with Ukyo saying she is now engaged to Ranma.
Unlike Ranma's other fiancees, Ukyo gets along with Akane well and is always friendly to her.