Second completed book of 2015 was the 2nd from Scott Lynch in his awesome Gentleman Bastards series. I'm still amazed he can turn the typical antagonist and make the reader invested in him/them. Cause they do very bad things. I guess it's cause worse things are often done to them. I had wondered how Locke and Co. would fare after the end of the first book. And generally... well. But it skipped a lot of post-book one events depression on Locke's part. That was shown later as flashbacks, which is a way of story telling Lynch dose well. And it included more flash backs to Locke's early training, as well. The world also got a lot bigger, and set up more hooks for more books.
I've already started book 3, and will be sad when I'm done and the 4th isn't out yet.