What the Sleigh? - Paranormal Protection Agency: Santa Elves, #3

Last Christmas... She didn't give him her heart. Because the b*stard broke it five years ago. Well, okay, it's been five years since were-reindeer Rudi left the North Pole and vowed never to have anything to do with Christmas again. Since then she's thrown herself into her work as an operative with the Paranormal Protection Agency and become one of their most trusted operatives. Until someone decides that the holiday season is the perfect time to pull armed heists on a few Santa's Grotto's in the city and relieve some parents of their valuables...
But the very next day... True-blooded Claus elf, and grandson of the original Santa, Nick Claus, knows how well and truly he's screwed things up with Rudi. Not only did one mistake lose him his lover, his childhood sweetheart and his best friend, but now all of the reindeer at the Pole hate him and draw straws to see who has to pull his sleigh. After five years though, he's managed to track her down to the PPA and he's determined to win her back, even if he has to go undercover as Santa to do it.
Unfortunately there's an armed gang looking to make a killing, maybe literally, and Nick has to make a decision... Save Rudi or be Santa. He can't have both.