Toil and Trouble. Modern Magick, #2

As an agent of the Society for Magickal Heritage, I, Cordelia Vesper, have an important job: rescue endangered creatures, artefacts, books and spells wherever they are to be found. It's a tough job, but somebody's got to keep British magick alive. So we rescued a valuable book from a long-lost library, only it proved to be unusually... chatty. And it's got a foul mouth, too. What manner of weird magick is this?Somebody else thinks it's pretty interesting, too.
Ancestria Magicka, they call themselves. Brand new. Big trouble. But why are they so interested in the book's creator? The woman died six hundred years ago. It's grave-robbers, necromancers and thieves all the way, and when things get that kind of crazy, there's only one thing to do. Call in the Toil and Trouble department.