She is a first-year student in the same class as Natsuki. She has an interest in Natsuki and believes she can read him by looking at his eyes.

Spoiler

When Natsuki forgot his lunch, she lent him money to buy a hot dog. When Natsuki forgot his umbrella, she offered a pink one with bunnies to him to use. She mistakenly interpreted Natsuki's love-struck look at Haruka to be directed at herself and thinks Natsuki has feelings for her.

(Source: Wikipedia)