Prologue: Childhood
Kana was an actor since she was three years old, also known for being a prodigy. Her talent gave her the nickname, "The genius child actor who can cry in ten seconds flat." This reputation would cause her ego to rise -- most prevalent when Kana first met Aqua and Ruby on set for a low-budget film. She was cold to them and even insulted their mother over her lack of screen time in a television drama stating that her acting was horrible.
Her ego would later crumble after acting side by side with Aqua -- acting much more creepily comparatively to her performance. Unable to accept that her acting was inferior, she cried to the director, Taishi. She begged for another take to make up for her supposed inferiority. She would never forget the day she was outclassed by Aqua.
Show Business
Kana adapted her acting style to put others in the spotlight, intentionally diminishing her skills for the sake of larger productions. She had to take odd jobs like Pepper Workout to remain in the entertainment industry, but her persistence led her to reunite with Aqua and Ruby at the same high school.
During the "Sweet Today" adaptation, Aqua noticed she was holding back on her acting skills to match her co-actor's level and reach the production's objective. She had always wanted to go all out but could not due to her fear of her past repeating itself. However, at the grand finale of the production, Aqua created an opportunity for her to perform at her best. This has led to her forming romantic feelings for Aqua.
After she and Aqua performed a grand finale for an adaptation of the manga "Sweet Today", she was called upon by the two siblings to ask if she could join the in-the-works revival of B-Komachi. Although initially against this due to the immense risk that could potentially ruin her acting career, Aqua's persuasiveness made her cave into their demands, calling her cute and believing in her potential.