A cyprianus, also called a black book, is book that holds medicinal knowledge, spells, information about deals with the devil, curses, blessings, and dream symbolism, among other things. Hundreds of cyprianus-books have been found throughout Scandinavia, hidden under floorboards, under the roof, and in the back of book collections. Back in the day, owning a cyprianus was very dangerous, as is could lead to trial and, in worst case, execution, if one was found to be performing magic. Thankfully, we're living in a more forgiving time now.