The Bone Dealers

From the PDF: The terrible incidents involving the vrykolokas served to reinforce Reginald Preston’s belief that a clear and dire danger to humanity exists. This belief has led Preston to increase his efforts in learning more about the nature of the danger. Unfortunately, his studies of the tome (the Notes on Magic) located by his ill-fated friend Don Wedenberg have lead him on a dangerous path. After mastering the ritual to Call Up Dwellers of the Charnel Yard (Contact Ghoul), Preston elected to attempt to contact these dwellers and learn from them as much as he could.