The Soul Guardians series does not have a new book coming out soon. The latest book, Seals (Book 8), was published in March 2015.
The first book in the Soul Guardians series, Marked, was published in March 2011.
The Soul Guardians series primarily falls into the Action Adventure, Science Fiction and Fantasy genres. This young adult series was written for ages 12-17, but can be enjoyed by adults too.