Haruka Amano is the granddaughter of the eccentric Professor Hiroshi Amano and the cousin of Kenta Amano. Because her parents work abroad in Germany, Haruka lives at her grandfather's laboratory, where she quickly assumes the responsibility of managing the household. Unlike her easily distracted grandfather, she is highly organized and capable, taking charge of all the housework and even managing the laboratory's finances to keep things running smoothly.

Possessing a forceful personality and notable maturity for her age, Haruka is often the voice of reason who keeps both her cousin Kenta and the professor in line. She is not afraid to speak her mind, particularly when dealing with the frequent and often unwelcome intrusions of Inspector Satsuda onto the Amano property. While Kenta tends to be more physical and impulsive, Haruka is studious and has an aptitude for technology, often seen working with computers in the lab.

Her relationship with Yutaro Katori, the android inhabited by the space police officer Fighbird, is a central aspect of her character. Haruka was the one who designed Katori's human appearance, giving him his distinctive look. She often treats Katori like an older brother and takes it upon herself to help teach him about human customs and life on Earth. However, her feelings are more complex than simple sibling affection, as she also harbors a romantic crush on him. This is powerfully demonstrated when she cries heavily upon seeing Katori's android body destroyed in battle.

While Haruka is not a frontline fighter, her role as a member of the Space Guard is indispensable. She works alongside Professor Amano, providing crucial support from the sidelines. Her intelligence and technical skills contribute to the development of new weapons and strategies to combat the forces of Emperor Draias, making her an integral part of the team even without direct combat abilities. Additionally, she has a pet monkey named Champ, who was a gift from her parents.