Widdershins by Jordan Hawk

Love is dangerous. Ever since the tragic death of the friend he adored, Percival Endicott Whyborne has ruthlessly suppressed any desire for another man. Instead, he spends his days studying dead languages at the museum where he works. So when handsome ex-Pinkerton Griffin Flaherty approaches him to translate a mysterious book, Whyborne wants to finish the job and get rid of the detective as quickly as possible.

Griffin left the Pinkertons after the death of his partner. Now in business for himself, he must investigate the murder of a wealthy young man. His only clue: an encrypted book that once belonged to the victim… Read more.