Starry Knight, ( The Knights of Avalon #1) by Nina Mason.

British aristocrat Vanessa Bentley has beauty , fame, and fortune, but she gets no respect for her decision to become a paranormal investigator. Determined to prove the naysayers wrong, Vanessa ventures to the misty moors of Caithness, Scotland. There stands the immense Castle Barrogill, where a vampire is rumoured to be stalking the dungeons- a vampire Vanessa is determined to find. She´ll just have to get past the resident shape- shifter. ...

Callum Lyon is the gorgeous reclusive astrologer and faery knight who guards the castle. For free- spirited Vanessa, seducing him proves easy. After all, he was once a breeding drone to a Queen. But astrologically, their differences are harder to overcome. Will Vanessa´s mission--and Callum´s secerets-- be more than their burgeoning love can take? Or will flesh--and blood-- win over the ghosts that haunt them both?

           

Callum our hero died on Flodden  Field. He was an astrologer to the Scottish King. The alternative "life".as a Knight of Avalon,  he was given didn't quite work out as he thought. Hundreds of years later he is hiding from his Queen, who thinks he is dead.

He is still an astrologer,  but everyone knows now that is just rubbish. He is also a shifter who needs blood and sex to survive. 
Vanessa is rich girl from an unhappy family.  She is determined to never be tied down by any man. Love is just a fairy tale. She has been able to see ghosts since she was a child, and now is going to use that as a new career. The way to start that is to investigate the vampire said to be at a certain Scottish castle.
The main story line is great. Our hero is a very sexy shifter, even if he is a bit chauvinistic.  Our heroine is trying so hard to be independent she could lose the best thing to ever happen to her. 

I found this just a little long winded in places. I love a long story, but this seems to stretch out unimportant parts and not cover what I think should be covered. I feel that the reason he has a problem with the Sinclair clan should have been explained more , as it pays a role in his present "life".
I will still read any follow up stories. 

 Nina Mason ia a hopeless romantic with strong affinities for history , mythology, and the metaphysical. She strives to write the same kind of books she loves to read: those that entertain, edify, educate, and enlighten. Her genres include erotic paranormal and historical romance. She has also written a political thrillers. Born and raised in Southern California, she now lives in Woodstock, Georgia, with her husband, youngest daughter, two cats, and a Westie named Robert.