The second book in the series, Not Exactly Innocent, is free for Kindle today. Its run as an Amazon ebook exclusive ends tonight, and so it should be available again at Smashwords by tomorrow or the next day. It won't be free there, though. To get it free today, go to Amazon, specifically to https://amzn.com/B00JYN07M0.
(I can't get the 'link' feature here to work today, so please bear with me, as I just plop links down out in the open instead of incorporating them into the text. I know it looks clunky. But the system simply isn't working right today, and I'd rather have clunky links than none. Silly me, I know.)
The other books in the series are Not Exactly Allies, Decidedly Not Official, and Not Quite Home. The common thread in all of them is Richard Hugh, who starts off as a dedicated bachelor intent upon saving civilians from bad guys, and winds up as... Hmmm... No, I think I'll let you find out what happens to Richard on your own, if you are so inclined. Wouldn't want to give you any spoilers... ;)