One night in a merchant's mansion, a kunoichi (female ninja) named Yasuzu
is violated by a group of men under the effect of "Aura of Ogre", called "Demi-Ogre".
Although she had kept her virginity, the Demi-Ogres keeps sexually tormenting Yasuzu.
Now the only thing Yasuzu can think about is her senior kunoichi Botan who she has longed for.
