Hungry Souls:

Hungry Souls Supernatural Visits, Messages, and Warnings from Purgatory By: Gerard J. M. Van Den Aardweg

Non-fiction: Religion 151 pages

Book Count: 18

First a religious book of ghost stories is either the most boring book of ghost stories, or inversely the scariest. It's not scary as it is all true stories most with some level of documentation and often told by religious people who gloss over all the strange noises, moving objects, odd dark humanoid forms that make ghost stories scary. (Not that the author isn't saying that those things and other things that people think about when talking about ghost or even other paranormal events aren't true. As he is.) But it is also the most scary in that the ghost often describe their suffering in purgatory, or in one case Hell, which is worst then some dead guy jumping out and yelling "Boo!"

As you can tell this book is mostly a theology book that deals with the afterlife by telling stories of people that came back. Some stories are from near-death experiences, some from souls in Hell or Purgatory, and a couple from Heaven. It also deals with the Purgatory Museum in Rome, which is a part of a church that has things like prayer books with hand prints burned into them from visions/ghosts/souls of people in Purgatory. Mostly it’s a lot of dead people asking family members or holy people to pray for them, and then some important theological information relating to their requests.  It has a large number of in depth footnotes and also a bibliography of books in multiple languages.  Also although unlike many religious books having to deal with ghosts it’s answer isn’t “they are all fakes” or “they are all demons” it does point out that like all supernatural visions and visits it’s not something you should try and force to happen by doing things like going to a psychic.