Ikusa Otome Valkyrie / Ride of the Valkyrie

Valkyries are virgin warriors from the Norse god, Odin, plus they protect the humans from demons with the outskirts. However the demons are finding the Valkyries' weakness following your betrayal with the goddess, Freya, becoming a sex slave. Thus one Valkyrie was made a sex slave after being threatened that her kinsmen will share the identical fate if she did not submit. With the castle bought out, the demons challenged each of the men to impregnate her, if they would like to live...