Born into Frysian nobility, Jackie has spent her life burdened by impossibly high expectations due to her older sister Amicia's reputation for perfection. Her family's complex history includes an older brother who joined the rebels and was subsequently disowned, creating a legacy of political rebellion that she's both drawn to and trying to escape. Despite growing up in comfort, she feels a genuine connection to the cause of justice for the Frysian people, much like her sister, Amicia.

Jackie's personality combines high intelligence and analytical thinking, particularly with technology, with empathy and pragmatic approach to problem-solving. She maintains remarkable composure under pressure and possesses an observant eye for subtle details and power dynamics that others might miss. Though she maintains emotional distance from the team, she often serves as the voice of reason and strategic thinking in difficult situations.

Her motivations center on restoring her family's honor and gaining acceptance as royalty by the Olympian empire, while also proving herself apart from her sister's overwhelming shadow. She wants to ensure the Millennium is used ethically and seeks to find her place between noble obligations and personal convictions. Her relationship with Axel reveals an intellectual bond and subtle attraction that she keeps carefully hidden beneath professional respect.