She is seen by other girls as being strong, refined and genteel, however they become surprised when they realise that Fumi is actually very gentle and shy. Others have noted her for having pretty eyes and a soft, lady-like voice. She is often said to make "scary faces" when she is upset or irked. Despite her size, mature aura and sometimes foreboding presence, Fumi is a reserved crybaby.
After moving back to her home town, she makes fast friends with a girl from her youth: Okudaira Akira. Fumi used to live nearby to Akira growing up, and so they were best friends from the young ages of five or six. Fumi relied heavily on Akira in kindergarten, as she is seen incapable of doing anything but crying until Akira comes to "save" her and take care of her. This has not changed much as she got older, as noted by Akira.
Fumi has had a close relationship with her older cousin Chizu. She even implores Chizu to stay with her for a few more days in her new town. Fumi does not seem to welcome the move back, and wishes that she could have stayed in her old town with her cousin. In a turn of events, it is revealed to Fumi that Chizu is to be married. Fumi harboured deep feelings for her cousin who was aware of this. She sees this as a betrayal of trust as Chizu neglects to even inform Fumi of her engagement.
She has a secret that she tries to keep bottled up to herself, though she later reveals it to Akira. It is evident that Fumi likes other women though she is still very much in the closet. She even hesitates to tell Akira this bit of news, though Akira accepts Fumi as she is, much to Fumi's relief.