The forest.
One bright afternoon a young girl takes a walk.
She is pleasant to look at, beautiful in kimono and nice hair and makeup.
"Little girl..."
Somewhere, a voice calls to her.
"Hey little girl."
There's no one around.
She's alone. Not even a beast or bird has been seen.
"I am the Butterfly. Remember me now."
The strange voice sends a chill up her spine and down the length of her sword.
The sword that was once a demon, transformed by a promise she made.
The sword called OniKiriMaru.

As the forest closes around her, the girl has no choice... but to face the dance...

[From DLsite English]