Age: 15
Birthday: March 2
Horoscope: Pisces
Height: 163 cm
Blood Type: A
Family: Father, mother, older sister
Liked foods: meat, potato chips
Disliked food: entrails
Specialty: Mimicking machine gun sounds

Hirose is kind-hearted, friendly to all and sweetly optimistic. His honesty and cheerful demeanor is apparent in everything he does, even to a childish extent at times. When provoked, he becomes agitated, and this honesty leads him into trouble.

He is a health committee member at school and is shown to be readily helpful to those who need him. He is largely sympathetic to most, but this considerate side of his causes him to struggle with expressing his real, not always agreeable feelings.

Hirose has exceptional memory, with many characters, especially Nakamura, being surprised at the level of detail he remembers. At school, he admires his teacher Otogiri-sensei for being "cool."

He is the person who Nakamura holds great affection for.