Rory by Hazel Hunter

From paranormal investigator to the disappeared, a social media star goes exactly one step too far.
Harper Ensley has chased down too many ghosts in too many haunted places to be warned off McKeran castle. But the dreams that have plagued her since her visit to the highlands have her on high alert. Even so, nothing can prepare her for what awaits at the end of the torchlit corridor.

Rory McKeran stands out from the rest of his clan by any measure: the largest, the least talkative, and the most solitary, even after nine hundred years. He has his reasons, of course, but when Harper arrives, they are swept aside as the pair are irresistibly drawn not only to each other but also the impending doom of the clan.
As enemies assault them from without and within, the pair must risk everything to survive.