The Queen serves as wife to Silverland's King and mother to Princess Sapphire. She champions the concealment of Sapphire's biological sex from birth, a necessary deception mandated by kingdom succession laws barring female heirs. This prevents the corrupt Duke Duralumin and his son Plastic from seizing power, though the Queen endures profound personal sadness over her daughter's inability to live openly as a girl.

Her emotional struggle deepens as Sapphire matures, fueling a persistent desire to publicly reveal her daughter's true identity, born from witnessing Sapphire's dual existence and its inherent risks. The antagonists exploit this vulnerability; Baron Nylon drugs the Queen, causing her to unintentionally disclose Sapphire's secret during a public gathering. This forced confession results in the Queen's arrest alongside Sapphire on treason charges, directly escalating the kingdom's political crisis.

Throughout the ensuing conflicts and Sapphire's efforts to protect Silverland, the Queen remains a steadfast supportive figure within the royal family. She provides crucial emotional stability during captivity and political upheaval. She remains visible within the palace environment, often alongside Sapphire's caretakers, reinforcing her role in the narrative's domestic and emotional dimensions.

Across subsequent manga serializations and the television adaptation, no significant deviations or expanded background for the Queen are documented. Her narrative purpose remains anchored to Sapphire's secret and its political repercussions, without additional development in spin-offs or alternative media.