–It was on that day that “normal life” ceased to be normal.

Kou Tokisaka is an ordinary high school student living in Morimiya City, which is located on the outskirts of Tokyo. One night, while returning home from one of his many part-time jobs, he stumbles upon an “incident” in one of the dodgier parts of town.

Asuka Hiiragi—

The beautiful and intelligent student body president who just recently returned from an extended stay overseas. She was being surrounded and harassed by a couple of degenerate lowlifes who were trying to force her to go with them.

“What in the hell is she doing HERE of all places…?!”
As annoyed as he was, Kou wasn’t so irritated that he wasn’t willing to chase them down.

And what he saw wasn’t what he was expecting—
A terrifyingly compelling form shimmering in the air that obviously wasn’t of this world, two fear-struck delinquents about to be devoured by some kind of horrifying monster, and—

–Hovering like an angel,
A figure of a “girl” wielding a “sword” gleaming with an unearthly blue light–