くノ一葵、悪ニ堕チル

Kunoichi, female ninjas that act for the sake of justice
from behind the scenes.
Kagehana-kumi is a team of three kunoichi.

Aoi Ukyou, the leader of the team, infiltrated into a mansion of Kurokawa, a suspicious local governor.
Then Aoi was caught by Maya, the daughter of her target.
Unable to commit suicide, she was tortured and violated...

On the other hand, Tsubaki and Houki, the other two of the team,
thought Aoi failed in her mission because she did not return in time.

They didn't know that Maya was on their track...

Kunoichi try to resist the brainwashing. Weakened by the assaults such as public nudity, sexual training, humiliation, etc., they gradually give in...