The Hell You Say — Josh Lanyon

The third novel in the Adrien English series finds the "ill-starred and bookish" mystery writer and bookseller battling demons--maybe literally. After bookstore clerk Angus flees following terrifying death threats, Adrien must contend with a mysterious Satanic cult, a hot and handsome university professor, and his on-again/off-again relationship with closeted LAPD Homicide Detective Jake Riordan. And, oh, yes, murder...