Invaders of the Rokujouma!? Volume 16

With things coming to a head between the radical and conservative factions, it's time for Kiriha and the others to take a stance. After discovering a cataclysmic weapon in the hands of the radicals that stands to threaten both the surface and the underground, can they act in time to prevent tragedy? The clock is ticking, but it won't be the only thing working against them since the radical faction has a little... outside help... on their side.