The gateway to the netherworld continues to expand to the point where it has started to consume the real world. Complete demise creeps ever closer as time passes. After miraculously managing to rescue Hiyori, the girls prepare to face Princess Tagitsu with the hope and fate of the world resting on their shoulders.
The threshold between our 
world and the netherworld.
.العتبة بين عالمنا والعالم السفلي
Die Schwelle von unserer Welt
zur Unterwelt.
La frontera entre nuestro mundo
y el inframundo.
La frontera entre nuestro mundo
y el inframundo.
Il confine tra il nostro mondo e gli inferi.
É o limiar entre nosso
mundo e o mundo inferior.
Промежуток между двумя мирами.