Laura Fukuōji is the 14-year-old heiress to the wealthy Fukuōji Zaibatsu, which owns a world-class shopping mall and a local mansion. Of half-French heritage, she has blonde curly hair styled to chest length and blue eyes, occasionally using French phrases like "Tres bien" and "S'il vous plait". Returning to Japan from France, she reconnects with her childhood friend Airi Kirara. Despite her family's immense wealth, including a skyscraper residence and the ability to commission Hollywood films, Laura possesses one unattainable desire: Airi's older brother, Sakutarō Kirara. Her singular obsession began in childhood when Sakutarō saved her after a failed flying machine experiment, solidifying her romantic admiration, though she often frames it as wanting him as her "big brother". Laura maintains an entire room dedicated to Sakutarō memorabilia, filled with photographs and personal items. She teams up with the Jewelpet Luea to steal Airi's magical pendant, believing its power can force Sakutarō to return her feelings. Their schemes involve gentlemen-thief outfits and burglary attempts, like infiltrating the Kirara Detective Agency's rooftop. These plans frequently fail, often resulting in Sakutarō rescuing Laura—repeating their childhood dynamic and deepening her infatuation. Beneath her comically single-minded pursuit, moments reveal Laura's vulnerability about her parents' constant absence. She bonds with Airi over shared loneliness during an exchange involving character bentos, and interactions at her mansion's pool illustrate her capacity for genuine connection beyond her primary fixation. Laura's development centers on her evolving strategies to win Sakutarō's affection and her reluctant partnership with Luea, with no significant resolution to her romantic pursuits within the available narrative.