Mirai Asahina, a 13-year-old girl who's going into her second year of middle school, witnesses a mysterious object fall in to the park. Excitedly, she brings her stuffed bear Mofurun with her to see what it was. When she gets there she sees a girl named Riko flying on a broom. Mirai has a lot of questions, and Riko explains that she's searching for...