This is book 1 in the series and Wild Rain is book 2.  If you buy the book Fever, you get both books in one edition.  I love this series.  As typical of a novella, this is good but not as well developed as I'd like.  Pair it with Wild Rain and the Awakening is a great start to the new series.  I've read these as paperbacks.  I've been running out of space at home so as my budget allows I've been going back and purchasing favorites I like to re-read.  This series is one of the series I like to re-read.  Enjoy a great read!