There Are No Saints by Stephen Kanicki

In the summer of 1857, the Devil visited Titusville, Pennsylvania and was greeted by an exorcist with a drinking problem and a bad attitude. This is his story:

For the low price of five dollars, Dexter “Dex” James will exorcise your demons: the demon of lust, drink, and gluttony. Unfortunately, he’s new in town, and few people take him seriously. The ones that do, don’t have a dime to spare. Desperate for money, he elicits help from a boy named Boo and a beautiful woman, named Miss Leslie—she’s half his age and a prostitute, but Dex is smitten.

After performing a supposed miracle, Dex becomes the talk of Titusville. His billfold and ego grow with each exorcism. Only Miss Leslie’s love could make him happier. However, when an evil entity threatens a young girl, Dex must make a choice: take the coward’s way out or stay and fight?