False Book

False Book is one of the magical items described in Monster Girl Encyclopedia World Guide III: Sabbath Grimoire.

Guide Book Entry
A magic book that cannot be correctly read by a person who does not meet the requirements. For example, in the case of a "False Book" with the condition of having a certain degree of mamono mana in the body, it becomes a book that can only be read by mamono, or the incubi that are their companions. Should another view the book, both the binding and contents of the book cannot be correctly recognized, it looks like a book of nonsense sentences or a blank book, and there also exist those made with a more complex technique that look like a completely different book.

Various requirements can be added depending on the technique, such as those that can only be read by men who were tempted and fascinated by mamono, and women that are turning into mamono, or those that can only be read by a specific race of mamono or human of a specific bloodline, it can also be a more complex requirement, such as a book that can only be read by those among human women that have a high quality to become a specific race of mamono.

Many Sabbath-related books, including this book, are "False Books". They can only be read by mamono, incubi, or those that have already had their hearts snatched away by mamono. Even if the book you are now reading is found by members of the church, you can be relieved because in their eyes they can only see the bible of the Chief God.

Usually, this magic tool is said to be used with the intention of "falsifying the appearance so the existence and contents of the book are unknown except to specific people", however, there are also some made with the intention to "slip in another book by falsifying the appearance". For example, the "Scripture of the Fallen God" is slipped into the many "Scriptures of the Order of the Chief God" that exist around the world. Since they falsify their appearance as the scripture of the Order of the Chief God, no one notices their existence, and so the "Scriptures of the Fallen God" said to stain you with the teachings of the Fallen God if you read it continue to exist in the libraries and archives of religious nations throughout the world, waiting for the time when those possessing demonic qualities take it into their hands.