One Day

The sky split and the earth cracked. Heaven and Hell merged with the mortal world! But it was more peaceful than expected. Angels and demons were generally friendly and blended into modern society. However, their concept of death was extremely loose. They possessed a gag-manga-like healing ability where they could recover from the brink of death just by sleeping until the next day. Furthermore, the demons—as one might expect—became obsessed with human firearms. They're loud, powerful, and above all, cool! Companies noticed these angels and demons and, pouring fuel on the fire, started saying, "Let's authorize armaments and turn it into entertainment." The government's attitude was a dismissive, "As long as people don't actually die, right?" It didn't sound like a government, but they weren't strong enough to talk back to demons.

A Chaotic Japan.

A little time has passed since the worlds integrated. Demons who can't adapt to the environment and angels who were already mentally unstable have started appearing here and there. As these girls flowed into the cities, the concept of "Jirai" (landmine/unstable) quickly took hold among the demons and angels. This is a story involving such girls.