Introducing Rima Mashiro (真城 りま, Mashiro Rima)

Rima Mashiro replaces Nadeshiko as the new Queen's Chair. Although Rima is the same age as Amu, she is extremely petite and has relatively poor athletic ability. Most of the boys in her class admire her because of her beauty and passive personality, while the girls are annoyed by her because of her selfishness.

Because of a kidnapping incident that happened before she transferred to Seiyo Elementary, her parents pick her up after school, but since it interferes with their work schedules, they often argue about who cares more for Rima over work, resulting in Rima often having no one but Kusukusu as company for her secret interest in gag comedy. Later, she opens up to Amu and becomes friends with her.

When Yaya explains to Rima about Amu and Nadeshiko's friendship, she appears to be jealous. At first, she is shown to have great dislike for Nagihiko because Amu told Rima and Yaya that he is Nadeshiko's twin brother due to a confusion between the two. That leads Rima to be protective over Amu. She tells Nagihiko that he is useless because his Guardian Character is still inside an egg, but gains respect and trust for him later on. Rima discovers that Nadeshiko and Nagihiko are actually the same person. She performed a join attack with "Nadeshiko" called queen's waltz. In the anime television series, Rima is voiced by Sayuri Yahagi. She is portrayed by Karen Yagishita in the musical.