TV-Series
Description
Fuuka Matsui is a classmate of Sana Kurata and Akito Hayama upon starting junior high school. She first meets Sana in the school bathroom on their initial day, and the two swiftly form a friendship, bonding over their nearly identical appearances and similar personalities. Fuuka possesses short dark brown hair, round brown eyes, and shares the same height and body shape as Sana, leading both to believe they look alike.

Having spent many years in Osaka, Fuuka speaks with a distinct Kansai accent, which occasionally becomes a source of teasing. Her personality is sassy, self-assured, and quick-witted. She is hyper and energetic, much like Sana, though generally calmer, more serious, and less naive. She shows courage by standing up to Akito when others refrain and excels as a student with skill in gymnastics.

A significant event from her past involves an incident in kindergarten, where Akito Hayama was dared to kiss her for 60 yen, taking her first kiss. Later, while in Osaka, she told elementary school friends about the kiss but omitted that it occurred in kindergarten. This led to rumors she had a boyfriend, causing her crush, Yuta Takaishi, to avoid her. Fuuka blamed Akito for complicating her relationship with Takaishi and disrupting her life.

Upon entering junior high and discovering Akito attends the same school, Fuuka openly expresses her hatred for him. Her perspective shifts after witnessing an interaction where Akito declines a girl’s request for a picture and explains his reasoning about honesty and not pretending kindness. This sparks her interest in him.

Later, Fuuka receives a call from a friend in Osaka and, not wanting to seem dateless when meeting Takaishi—who now has a girlfriend—she asks Akito to pretend to be her boyfriend. After this encounter, she requests that he become her real boyfriend, and they start a relationship while Sana is away filming a movie.

During their relationship, Fuuka develops genuine feelings for Akito but notices he remains distant. She observes that he does not kiss her even when their faces are close, unlike his behavior with Sana. After Sana returns and rumors about her dating her costar are dispelled, Fuuka realizes Akito and Sana still share mutual romantic feelings. Tsuyoshi Ohki informs Fuuka about Akito and Sana’s shared past and deep connection. Understanding that Akito needs Sana, Fuuka decides to break up with him despite her own hurt.

After the breakup, Fuuka focuses on gymnastics. Sana later contacts Yuta Takaishi and learns he broke up with his girlfriend and still has feelings for Fuuka. Sana provides Takaishi’s contact information to Fuuka as a Christmas present. Though initially upset by the gesture, Fuuka feels happiness, and they eventually begin dating.

In the spin-off "Deep Clear," Fuuka makes a brief cameo as an adult attending a party celebrating the birth of Sana and Akito’s daughter, Sari, indicating she remains friends with them into adulthood.