Mifuyu is a high school student who lives in Yominaga-cho, a town full of books, and whose great-grandfather was the founder of the huge library, Mikurakan.
One day, when her father, who is her manager, was absent, a collection of books was stolen from Mikurakan, and Mifuyu sees a message left behind. "Whoever steals this book will be chased by the flag of magical realism." And the city transforms into a world of stories...!?
To save the cursed city, the girls' adventure begins!