Not here. Somewhere far away. In the middle of
such a world sky, one girl —— Waltz -- gets flown away in an accidental accident.
After her barely successful landing, she stops in an abandoned village, where she meets Lucia, a younger girl who was about to be attacked by demons, and tries to live quietly with her.
But Waltz's identity is a superweapon from the modern world. Sometimes
Lucia can use strangely strong magic, and it doesn't come true that they live in peace.
This is the story of them winding the world into a vortex of chaos.