Toranosuke's older sister is a former member of the Supernatural Studies Club. After learning about the seventh witch's name, Leona stops attending school in fear of the witch's memory wipe, and hangs out in her room where she types on her computer. She likes to use scissors like throwing knives at intruders.

She later reveals that Haruma and she were the former members, and that he told her to flee when he discovered the seventh witch's power.