Majo to Kuroneko: Kateikyoushi wo Shitara Kouman na Hime-sama ni Natsuka Remashita

Anne Doherty, a magic user called the Singing Witch, wanders from country to country accompanied by a black cat named Ruud, who is in truth her husband trapped in animal form by a curse. Word that the Kingdom of Bromelia may hold the key to undoing it sends her there with a recommendation from the International Magic Association, which lands her the post of tutor to the realm's third princess, Erika. The girl has already chased off roughly a hundred predecessors, but Anne refuses to be rattled by her hostility, and Erika slowly begins to lower her guard.