The story follows Issei Hyōdō, a dim-witted, lecherous second-year high school student who is killed by a girl on his first date ever. Issei is reincarnated as a devil, and from that day forward, he serves as an underling of Riasu, a high-level devil who is also the prettiest girl on Issei's campus.
Kraft Lawrence, a 25 year old peddler travelling from town to town selling and buying various things to make a living during a period much like Europe in the Middle Ages. One night when stopped at the town of Pasroe, he finds in his wagon a 250 year old pagan wolf deity girl named Holo. She appears to be that of a 15 year old girl, except for a wolf tail and ears. She introduces herself as the town's goddess of harvest who has kept it blessed with good harvests of wheat for many years. Despite having the responsibility to watch over the town, she wants to go back to her homeland in the north called Yoitsu, she believes the people have already forsaken her anyway and that she has kept her promise to maintain the good harvests. She manages to bargain her way out of the village by making a deal with Lawrence to take her with him. As they travel, her wisdom helps increase his profits, but at the same time, her true nature draws unwanted attention from the church.
In a world where dead people turn into books and are stored in the Bantorra Library where anyone who reads a book can learn their past. Bantorra Library is maintained by Armed Librarians who wield psychic powers and their enemy is a religious society known as Sindeki Kyōdan.