Nina Shimazaki

Nina is kind, observant and supportive. She spends considerable time with Hina through both their class and rhythmic gymnastics club, giving her opportunities to notice changes in her friend's behavior that casual acquaintances might miss.

She quickly recognizes Hina's interest in Taiki Inomata and encourages her. Her involvement is friendly rather than manipulative; she wants Hina to be honest about what she wants instead of suppressing her feelings.

Nina can approach romantic subjects more casually than Hina herself, providing someone with whom Hina can discuss feelings she struggles to express directly to Taiki.

Nina is a member of Eimei's rhythmic gymnastics club and practices alongside Hina. She participates in the same athletic environment, although the manga does not establish an individual competitive record comparable to Hina's national-level achievements.

Her role in the club confirms that she trains seriously in rhythmic gymnastics rather than merely accompanying Hina socially. She therefore understands the practice demands and competitive pressures that form a major part of Hina's life.

Outside sport, Nina's strongest established quality is social perception, particularly regarding Hina's emotional state.

Nina belongs to the Eimei friend group surrounding Taiki and Hina from early in the story. She shares Class 1-B with them during their first high-school year and had also been in Hina's class during their first year of middle school.

As Hina becomes increasingly aware of her feelings for Taiki, Nina recognizes what is happening and encourages her friend. This gives Hina someone within her own rhythmic-gymnastics circle who can respond to the romantic side of her storyline.

Nina continues into the characters' second year at Eimei, moving into Class 2-A and remaining part of Hina's social circle as their school lives and relationships develop.

Hina Chono is Nina's close friend, longtime classmate and rhythmic gymnastics teammate. Nina recognizes Hina's feelings for Taiki and supports her.

Taiki Inomata is Nina's schoolmate and the person at the center of Hina's romantic feelings.

Kyo Kasahara is another student within Nina's broader Eimei social circle and is likewise aware of the emotional complications surrounding his friends.

Chinatsu Kano is Taiki's upperclassman and romantic interest, making her important to the situation Nina observes through Hina.