The Marquise Gabrielle de Polignac, also known as the Duchess de Polignac, is a character in the anime Lady Oscar based on the historical Yolande Martine Gabrielle de Polastron. She is introduced as a young, beautiful woman with an angelic face, blonde hair, and light-colored eyes, possessing a charming and lively demeanor that initially draws Queen Marie Antoinette’s affection. Beneath this pleasant exterior, she is deeply ambitious, self-serving, and morally flexible. Her primary motivation is the pursuit of wealth, social status, and influence, both for herself and her family. In the story, she arrives at Versailles after Marie Antoinette becomes queen and quickly becomes the monarch’s closest friend and confidante. Exploiting this bond, she persuades the queen to indulge in lavish spending, gambling, and disregard for court etiquette, thereby leading Marie Antoinette down a path that contributes to the monarchy’s decline and the queen’s growing unpopularity with the French people. Gabrielle is also the biological mother of Rosalie Lamorlière, a child she bore out of wedlock and abandoned without support. When Rosalie later appears seeking revenge, Gabrielle initially shows a flicker of remorse but soon suppresses it, deciding instead to use her daughter as a tool for a political marriage. She treats her legitimate daughter, Charlotte, similarly coldly, pressuring her to marry an older, wealthy nobleman for family advantage, which ultimately drives Charlotte to suicide. Gabrielle views family members as pawns to be placed for her own benefit. She is openly antagonistic toward Oscar François de Jarjayes, the captain of the Royal Guard, because Oscar often thwarts her schemes and advises the queen against her influence. To eliminate this obstacle, Gabrielle does not hesitate to plot assassination attempts, such as arranging an ambush or tampering with a chandelier. She also manipulates court gossip and uses her network of relatives to secure lucrative posts and pensions. When the French Revolution erupts, she immediately flees France, abandoning her friend Marie Antoinette without remorse, and dies in exile. Throughout the series, Gabrielle remains largely static: her initial charm gives way to reveal her ruthless, materialistic nature, and she never undergoes a true redemption. Her notable abilities include her singing voice, which first captivated Marie Antoinette, and her exceptional skill in social manipulation, persistent scheming, and the strategic placement of allies at court.