Hoshino is a third year student from Ooarai Girls High School. Her height is 160cm and her blood type is type AB. She's also a member of the automotive club. She's also the gunner of the Leopon Team which only joined during the finals.
Hoshino is a girl with medium black hair and a pair of green eyes.
- Her favorite flower is Dandelion and her favorite tank is the Japanese Type 2 Ka-Mi.
- Her name is based on japanese Formula One driver Kazuyoshi Hoshino who participated in the japanese Grand Prix' 1976 and 1977.