Kaoru Hanano serves as one of the co-managers of the Tobita Crush Gear Club, sharing these duties with Lilika Tobita. She shares a long history with the protagonist, Kouya Marino, as both a schoolmate and childhood friend, having known him even before his friendship with Jirou Oriza was established.

Kaoru has reddish-brown hair that is typically secured in a high ponytail, and she possesses dark gray eyes. Her standard outfit consists of a green jacket layered over a lime green shirt with a white undershirt, paired with a blue miniskirt, long white socks, and orange shoes. During a temporary period when she leaves the Tobita Club to join the all-female Pink Lips Team, her appearance changes significantly; she wears a black leather jacket over a yellow shirt, a black skirt, matching boots, a red belt, and a necklace featuring a gold star pendant.

Personality-wise, Kaoru is known for having a notably short temper. She frequently reacts to situations involving her teammates by delivering swift strikes, often using kitchenware or her bare hands to express her frustration or discipline others. This behavioral trait continues consistently throughout the series, extending even to the final episode where she threatens the characters Jirou, Kyousuke, and Kuroudo after observing Takeshi Manganji becoming emotionally distracted during a pivotal match.

In her managerial role, Kaoru focuses on researching opposing teams and delivering tactical insights about rival Gear Fighters to her teammates during matches. A significant shift in her role and motivations occurs when she temporarily abandons the Tobita Club to join the Pink Lips Team following an argument with Kouya. This decision coincides with the Illusion Cup tournament, where her new team, Pink Lips, faces her original team, the Tobita Club. After both members of the Pink Lips Team lose their respective matches against Kuroudo and Kouya, Kaoru returns to the Tobita Club, honoring a pre-battle agreement made by Pink Lips member Momo Yamanoki.

The foundational relationship between Kaoru and Kouya persists throughout the narrative, enduring the temporary strain caused by her departure and subsequent affiliation with the Pink Lips Team before eventually resuming its usual dynamic. While the anime series does not depict her as a competing Gear Fighter, Kaoru does utilize a Gear named Kaoru-gia exclusively during training sessions within the Gear Champion League video game.