Sapphire first appears as the cross-dressing heroine in Osamu Tezuka's manga *Princess Knight*, her character shaped by Tezuka's childhood exposure to Takarazuka theater. She navigates her story by maneuvering between societal expectations and a secret identity, balancing royal duties while disguised as a prince. After starring in *Princess Knight*, she returns as a mother in the sequel *Twin Knight*.

Across Tezuka's interconnected "star system," Sapphire makes frequent appearances, notably within the *Black Jack* series. In these varied roles, she consistently embodies "the sorrows of women," portraying complex feminine experiences. Specific portrayals include a kindergarten teacher who dies shielding a student during a tunnel collapse, a woman using her beauty to climb fashionable society only to face abandonment and poverty, a nurse entangled in intricate medical ethics cases, and a wife enduring profound emotional pain. These diverse depictions highlight Tezuka's focus on her core identity as a woman confronting hardship, beyond her role as a swordsman.

In the special *Tezuka Osamu ga Kieta?! 20 Seiki Saigo no Kaijiken*, Sapphire joins an ensemble of Tezuka's characters for a New Year's Eve gathering. When Tezuka mysteriously vanishes, she actively participates in the investigation led by Astro Boy, collaborating closely with figures like Black Jack, Dr. Tenma, and Professor Ochanomizu to resolve the disappearance, reinforcing her place within Tezuka's expansive narrative universe.

Throughout her evolution from protagonist to supporting player, Sapphire maintains her association with themes of secret identity, resilience, and gendered challenges. Tezuka's portrayal persistently centers on her womanhood, utilizing her character to explore societal pressures and personal struggles faced by women within different contexts across his body of work.