This story starts within darkness ~Introduction~

Suddenly my eyes opened.
I got the feeling I had been having some kind of terrible dream.
Is it night…?
Or is it that my eyes were still blurry…?
I slowly returned to consciousness.
The space around me was pitch black.
I sat up, and felt a sharp pain in my arm.
Why was I wounded…?
Laid out all alone on a cold floor.
Surrounded on all sides by damp walls.
I couldn’t remember anything.
What was I doing in a place like this…?
Suddenly, I heard a sound.
From a short distance, a dim light- someone was here.
The light drew closer.
I could make out a woman’s figure.
Her short blond hair swaying.
Her tanned skin blending into the darkness.
And her deep blue eyes.
What was going on…?
The woman didn’t know the details.
Just that there had been a terrible earthquake, and we were trapped underground.
The woman had treated the wound on my arm.
Apparently I had been shot.

Who am I?
Why had I collapsed in this place?
Who had shot me in the arm?
What had happened up on the surface?

[Translation of synopsis from DLsite.com]