Gust's first PlayStation Vita game, Surge Concerto Ciel Nosurge, was announced as the first entry in a series of titles. Living up to that promise, Gust will be releasing a second volume shortly.
Dengeki PlayStation reveals a June 28 release date for Vol.2. We don't have details just yet, but it seems that the new volume will have additional characters.
We'll hopefully get specifics on what differentiates this from the first volume, which was released in April.