Anne Dorsey, the "Singing Witch," is traveling with her familiar, the black cat Ludo. Although Ludo has been cursed and turned into a black cat, he is Anne's beloved husband, and the purpose of their journey is to gather offerings to break Ludo's curse. Since the offering they seek is located at the Royal Palace of the Bromelia Kingdom, Anne is sent by the International Magic Association to serve as a tutor for the Third Princess Erika, arriving at the palace with Ludo. However, Erika is a problem child who has fired a hundred tutors so far…. Erika begins to open her heart to Anne, who remains completely unfazed by the princess's intense cold treatment――.