Maru and Kiriko travel through a Japan that has been transformed into a hinderland in search of heaven. Lead by the Kiru-ray's mark which they believe is the key to finding Heaven they head for the Nara facility of Takahara Academy. However, as they wander through the forest, they are blocked by a strange figure. Meanwhile, the actual Takahara Academy is sieged by someone, and the children are protected by their attackers. At long last, the two world's in this series are connected in this sci-fi survival drama!