It's been six months since the events in Zettai Ryouiki no Tobira. Since then, several worlds with live civilizations besides EDEN and NEUE have been discovered, and the UPW (United Parallel Worlds) has been established.
The Luxiole, with the Rune Angel Troupe, Coco as the acting captain in Tact's absence, and Tapio Ca, the new Chief Operator, has been transfered to the UPW, and to them joins Roselle Mateus, the pilot of the prototype of a mass production Emblem Frame. However, when the Arms Alliance, commanded by the Three Marquises, declares war on Seldor and the allied NEUE worlds and damages the gate, the stranded Luxiole must face them alone.