In Death by W. M. Fawkes

Robin Dubicki almost lost his best friend to cancer last year, but everything changed the night they met the mysterious tall, dark, and handsome Doctor Sexy. Now, Timothy’s different. The sports-loving, sunshine man who was always at Robin’s side is now attached at the waist to his new boyfriend, and Robin’s convinced he’s joined a cult. Why else would Timothy refuse to go out in the daytime?
While Luke’s friend Michael is immersed in taking care of his new boy, Luke is the only one to notice Timothy’s best friend investigating. If he’s not careful, the young man’s going to get himself killed digging for dangerous secrets.
When Robin puts himself right in harm’s way, Luke has no choice but to act, and this loner vampire and lonely boy will find the connection they’ve both been looking for—if Robin can break free of a rival vampire trying to manipulate him.