Invaders of the Rokujouma!? Volume 29 by Takehaya

After getting back from Forthorthe, everyone was hoping they could spend their days in peace for a change. But as if the politics of the official Forthorthian invasion weren’t enough, something very strange and very unsettling is starting to happen around Koutarou and the girls. One mysterious disappearance becomes two, and there’s no clear cause or end in sight. Can they figure out what’s going on in time, or will Koutarou end up just like he was in the beginning—alone?