Hina was always an extremely sporty person who loved to exercise, and participated in many team sports during her school career, including track, basketball, softball, volleyball, tennis, and her favorite sport: competitive swimming. Since elementary school, she broke records in every swimming contest she entered, and was chosen to become an Olympic cadet. Her younger brother Yuta was also a competitive and talented swimmer, but not - by his own admission - as talented as Hina.
Hina attended Asanaro High School, and was later scouted Hope's Peak Academy as part of Class 78th as the Ultimate Swimming Pro.
Hina is 18 years old, (160 cm) 5'3" and weighs around 50kg with a lean but curvaceous build. She has brown skin, blue eyes, and wears her brown hair in a very high curled ponytail accessorized with a paperclip-style barrette. She wears Hope's Peak Academy-branded blue dolphin hotpants and green sneakers, a white tank top, and a red tracksuit jacket with white piping and her previous high school's logo on the chest. She wears knee-length white socks, a red knee brace over her right knee, a band-aid on her left knee. While swimming, she wears a typical high school girl blue swimsuit with her last name in kanji on the front.
Hina is a warm, cheerful, upbeat, and outgoing girl who is friendly and welcoming towards everyone she meets, trying to make friends with everybody and include them in her activities. Hina can be quite air-headed and forgetful, relying on the memory trick of writing peoples' names three times on her hand in order to remember them - a trick she also taught to her brother, Yuta. Due to being quite air-headed she can be easily manipulated by others and jump to conclusions or take them at face value. Hina is an extremely athletic person and considers it an absolutely fundamental part of herself, using it as an important coping mechanism in her daily life and feeling like she "might die" if she can't exercise. Although Hina is a star athlete in the running to become an Olympic swimmer, Hina is insecure that being athletic, which is seen as quite a masculine activity, makes her undesirable to others and might lead to her never finding love. She's also concerned that her extreme sweet tooth, particularly her love of eating donuts, is going to make her fat. She is extremely loyal to her friends to such a degree that when they are harmed it shatters her ability to emotionally cope.
Hina's athleticism is a core aspect of her personality and sense of self, and she participates in multiple sports including track, basketball, softball, volleyball, tennis, and her favorite sport: competitive swimming. Hina is a young Olympic cadet who aims to win a Gold Medal for swimming at a future Olympic games. Her younger brother Yuta, also a very strong swimmer, admits that Hina is a better swimmer than him. By her own admission Hina spends nearly all of her time training and trying to improve her fitness in some way, including wearing shorts all year round - even in winter - to build up her resistance to sickness, and practising the self-healing technique known as Kanpu masatsu.
For Hina, her love of sports doesn't come from her desire to win, but for the love of competing and striving to be better herself. In her own words: "What I really love about sports isn't winning, ya know? It's having to fight and struggle and give it all you got to reach the top. It's that excitement, that fear that you might suffer a heartbreaking loss. When you finally reach that goal, it's just...lonely. It's lonely at the top, ya know? So that's why I want to push myself as hard as possible when it comes to swimming. I want to aim for the very highest mountain top!"
Due to her fitness and athleticism, Hina is capable of holding her own in a fight if necessary. She is also much stronger than her small frame suggests, able to run at top speed for long periods of time while carrying the 52kg weight of Makoto Naegi on her back. She was also able to move a large piece of furniture that both Makoto and Ryota Mitarai could not budge even with their combined strength.