Suddenly Forever by Jerry Cole

Detective Aidan Kincaid couldn’t explain his stirring feelings for the beautiful young man whom he had seen mowed down by a car. But once he recognized his attraction, he fought against it because the victim of that crime was now also a part of his investigation. Besides, Dr. Riley Taggert probably wouldn’t see him as more than a fling. Funny how Aidan found himself hating that idea.
Bad luck had made Dr. Riley Taggert, research librarian at Warwick University, the target of a killer. It didn’t make sense. He was just an historian, a guy who loved old houses and was apparently easily bowled over by hot-as-fuck detectives with scars. What was a nerd to do when the cop in question only saw him as a part of his job? And how the hell was he supposed to avoid giving in to the chemistry between them? Damned if he knew!