Ruby, an Aurora Girl from Aurora Land, creates northern lights. Banished for selfishness and unacceptable conduct, she must locate the wish-granting Aurora no Shizuku stone—capable of three wishes—to earn forgiveness and return home, driving her initial quest.

Upon encountering Anpanman's group, Ruby falsely claims the stone is needed to save Aurora Land, concealing her personal redemption motive. This deception unravels when antagonist Baikinman learns of the stone's power and pursues it. Ruby then confronts a pivotal moral dilemma: use the stone's final wish to return home or aid her new friends against Baikinman, defining her character development.

This narrative represents Ruby's sole documented appearance across all franchise media, including television series, films, OVAs, and spin-offs. Her canonical background, storylines, and development remain confined to this specific movie.