Zero no Tsukaima -Maigo no Period to Ikusen no Symphony-

Louise and her friends are taken to a big library. It seems some ghosts often appear these days and they are asked to examine it. However, while they do examination, Louise suddenly disappears. She comes back a while later, but she becomes just a shy girl without heart.... They need to go into books and collect fragments of her broken heart, according to the caretaker. Like this, they decide to enter the book world....