He possesses exceptional physical abilities and absorbs lessons like a sponge, whether it's singing or dancing, leading to rapid growth. He is polite and always expresses clear gratitude after receiving help. He has a kind nature with consideration built into his character, often laughing off insults or being treated like a fool by those he considers friends. He has curly red hair. From the front, it looks like a normal short cut, but it is actually a two-block style with the back shaved short. He has blue eyes with a slight green tint. His sharp eyes give him a sleek and fierce image when expressionless, but since his eyes are on the larger side for this series and his eccentric yet kind personality is so prominent, most people find him cute rather than scary. There is a large gap between his expressionless face and his smile. Although he doesn't show much skin, his illustrations show he has a well-defined muscular build. Coming from a hometown where the law of the jungle still persists, he trained constantly to build his body, believing he couldn't survive if he wasn't strong. Despite his good physique, the reason he shows less skin than other characters is that he feels it is improper to expose himself to anyone outside his family. His hairstyle is a two-block and he wears earrings, which makes his design so unique one might wonder if he really just arrived in the city. However, since he was seen wearing earrings presumably from his hometown in childhood flashbacks, it seems he pierced his ears at a very young age. Although not explicitly stated in official materials yet, he is considered quite handsome. Having only recently arrived in the city, he lacks common sense and is ignorant of the ways of the world. His personality is so excessively honest and straightforward that he doesn't understand metaphors and takes everything others say literally. Before becoming an idol, he grew up in a place quite detached from modern Japanese society. The political system of the 'hometown' where the Amagi brothers grew up is a monarchy, and Hiiro, born as the second son of the monarch, was raised and educated from a young age to support the eldest son and next monarch, Rinne. Consequently, he lived accepting his role to absolutely obey his brother, protect him, and be his right hand. However, four years ago, Rinne suddenly left home, and eventually, when their father fell ill leaving the position of the next monarch vacant, Hiiro came to the city to bring his brother, who is eligible for the throne, back home. He then followed his brother Rinne into becoming an idol in the city.