Ikusa Miko Akari ~Akki Ninshin Ryoujoku no Utage~

A battling shrine maiden is a virgin who uses her holy power to fight against the teachings of the demons.
Akari is able to view her holy power as a halberd, and makes a living defeating evil spirits in various places for local warlords.
Travelling together with her band of female warriors, they would topple the demons that disturbed the peaceful world of Bikor, and save its inhabitants.
They were supposed to be a ray of light, hope in the darkness.
But when the people she wished to protect are taken hostage by the demons, Akari is led straight into their trap.
What awaited her was days of constant violation, until her orifices were overflowing.
Her little sister Koyomi, an apprentice shrine maiden, and the female warrior Shizuka, also fell in the hands of the merciless demons.
Stained and disgraced, Akari endured the treatment plotting revenge against the demons.
But her heart goes in the opposite direction, and she ends up seeking to server the demons with her body, instead...

[From dlsite]