Ann, also known as Mary Ann, operates as a space police detective within the Starry Sky World. Her central mission focuses on pursuing and arresting the phantom thief Blue Cat, whose true identity is Yuni in an alternate form. Despite her law enforcement role, Mary Ann’s absent-minded personality consistently hinders her ability to capture Yuni, resulting in repeated failures. Her activities unfold during an interstellar conflict where the Star Twinkle Pretty Cure team defends a mysterious creature named UMA against alien hunters. Mary Ann’s pursuit of Yuni directly intersects with this broader conflict, positioning her in opposition to the Precure team’s objectives.