Millefeuille Sakuraba is a seventeen-year-old girl with pink hair and blue eyes who serves as the first designated member of the Moon Angel Troupe and pilots the Emblem Frame Lucky Star. Her name is derived from the French pastry mille-feuille. She first worked as a waitress at a beachside cafe before joining the military, where she became the newest member of the Angel Troupe at the beginning of the series. Millefeuille possesses an extraordinary amount of good luck that often manifests in improbable ways, such as always getting all heads or all tails when flipping a coin, finding hidden treasure or winning lottery tickets, and remaining unharmed by gunfire, explosions, or even situations that would normally be fatal. However, this good luck is periodically balanced by episodes of extreme bad luck, which can cause catastrophic outcomes ranging from the destruction of a planet to the creation of a massive black hole at the center of the galaxy. The severity of this bad luck can be minimized if she is happy on those days, leading the rest of the Angel Troupe to mount operations specifically aimed at keeping her mood uplifted.

Millefeuille is naturally optimistic, carefree, cheerful, and selfless, always willing to help others without hesitation, even those considered enemies. She is described as ditzy and somewhat clumsy, often becoming the source of accidental misadventures through her luck, yet she consistently emerges from them unscathed. Her hobbies include making tea and cooking snacks, with a particular love for baking cakes and desserts. She also has a fondness for sweet foods and flowers, and the decorative flowers on her head can spin to allow her to fly or hover in the air.

Her motivations are driven by a genuine desire to support her friends and use her luck for good purposes, though her efforts sometimes backfire due to the unpredictable nature of her abilities. Within the story, she plays a central role as both a frontline pilot and a source of emotional warmth for the team. Her key relationships include a long-standing friendship with fellow Angel Troupe member Ranpha Franboise, whom she has known since military academy, and a close bond with her younger sister Apricot Sakuraba, whom she loves dearly and who looks up to her. In the manga continuity, she becomes the main character, forms a deep trust with Takuto Meyers, and eventually marries him, later taking on the role of gate keeper in the Galaxy Angel II storyline. Development-wise, while she remains consistently cheerful and altruistic across the anime, game, and manga versions, her role shifts from being a newcomer in the anime to an original founding member in the games, and to the protagonist in the manga. Notable abilities besides her luck include her piloting skills, culinary expertise, and the flight capability granted by her hair ornaments.