Rui Son

A well-known pianist in the world who is gradually making a comeback, Rui takes a liking to Chiaki soon after meeting him. Rui's appearance in Chiaki's life results in Nodame becoming jealous as well as insecure in her ability to perform on a level that will fit Chiaki's, particularly as Rui's fame unintentionally thwarts several attempts for Nodame to perform with Chiaki. Rui eventually decides to study music in Paris, though is met with opposition from her well-meaning mother, who pressures Rui to perform in more public performances. Though skilled, she lacks the style and substance of Nodame's performances and seeks to find the same element in order to improve her own musical ability.

She is actually in love with Chiaki. (Source: Wikipedia)