The core books is separated in three sections (100, 130 and 98 pages).
The fist section is the "In Nomine Satanis" background where players learn the evil side of the game with demons background.
The second section describes the core rules common to both sides.
The third section is accessible by reverting the book upside down and starting to read the last page as it was the first page. This section describes the "Magna Veritas" side with background on angels and good side.