Hina Fukami is the younger sister of Touko Fukami and a second-year student at Hinodehama First Junior High School. In contrast to her older sister, who can be somewhat absent-minded and dreamy, Hina is portrayed as a responsible, reliable, and down-to-earth girl. Her grounded nature makes her a pillar of support within her family, and she is often seen helping her sister navigate everyday situations and offering encouragement at important moments. She is also a member of the school's女子游泳部, the girls' swimming club, which adds an active and disciplined dimension to her daily life.

Within the story, Hina primarily plays a supportive role, though her perspective and daily life are given greater focus in the web manga Hina's Lip. She is a keen observer of the relationships around her, especially those involving her sister. Hina is a warm supporter of the budding connection between Touko and Kakeru Okikura, cheering for their relationship and hoping for its success. Her involvement extends to other members of the main friend group as well.

Hina holds a deep admiration for Yanagi Takayama, who is a close friend of her sister. This admiration leads her to pay close attention to Yanagi's personal life, particularly her feelings for Yukinari Imi. In a candid expression of her personality, Hina directly addresses Yukinari, telling him "please don't become uncool," a comment that reflects her honest and protective nature regarding those she looks up to. This moment shows that she is not merely a passive observer but is willing to speak her mind to encourage positive outcomes for the people she cares about. Through these actions, Hina acts as a subtle but steady source of stability and warmth, providing quiet support to the main cast as they deal with their own complex emotions and relationships.