Chiaki Sawada trains as a preparatory student at Kouka School of Musical and Theatrical Arts, specializing in musume-yaku roles within the all-female Kouka Revue tradition. As the younger twin of Chika Sawada, she shares a deeply close yet complex bond with her sister. Their mutual dream of joining the Kouka Revue ignited after childhood exposure to a performance starring bunny lady twins.

Naturally cheerful and expressive, Chiaki communicates with open honesty. Historically, her reliance on Chika to make joint decisions pressured her twin into prioritizing Chiaki's ambitions over personal desires, creating underlying tension. Chiaki remained initially unaware her dependence fueled Chika's sacrifices.

A defining moment unfolded during their Kouka School auditions: Chika passed the entrance exam immediately while Chiaki failed. Chika then deferred her enrollment for a year to retake the exam with Chiaki. This choice amplified Chiaki's guilt as she confronted how her setback altered Chika's trajectory. After both entered the school in their first high-school year, Chiaki actively recalibrated their dynamic. She cultivated awareness of her impact on Chika and deliberately pursued a more equitable connection.

Though their relationship thrives on profound nonverbal understanding, this intimacy once compelled Chika to suppress her own goals. Chiaki's growing self-awareness, honed through their school progression, gradually eased this pattern. The sisters now navigate healthier interactions while chasing identical performance aspirations.