Mayu Haruna is a supporting character in the anime Fuuka. She is the eldest sister of Yuu Haruna and also has two other siblings, Hibiki and Chitose. After their parents moved overseas for work, Mayu took on the responsibility of caring for her younger siblings. She works at an advertising agency in Tokyo and uses her income to pay the rent for the apartment where the family lives. Her personality is gentle and warm, and she has a calming presence that makes others feel comfortable. She is also patient and acts as a maternal figure within the household, keeping a close eye on Yuu and her youngest sister Chitose in particular. Mayu often addresses Yuu affectionately as Yuu-kun. Her primary motivation is to support her family and ensure that her siblings can pursue their own paths, including Yuu's growing interest in music. Within the story, she provides a stable home environment that allows Yuu to focus on his band activities without worrying about household finances. Though she does not undergo significant personal development in the anime, her consistent, caring nature makes her a dependable presence in Yuu's life. She does not possess any extraordinary abilities; her strength lies in her sense of duty and her ability to maintain a harmonious home for her family.