Invaders of the Rokujouma!? Volume 28

Now that Koutarou and company are back from their long journey to Forthorthe, everyone is hoping to settle back down into their normal, peaceful lives. Things are quickly thrown off course, however, when Theia, Ruth, and Clan show up with a little extra baggage and Koutarou suddenly finds himself in the midst of intergalactic negotiations. Has the real alien invasion just now begun? And what's with the strange voice Sanae keeps hearing? Moreover, what's got Clan so pensive?