Well, this is an idea, I had a while before. ^^ I'm not a big hentai fan, but they are quite amusing, especially the tentacle storys. And inspired by them, I thought about this story:
A girl (name is not important at all) summouns a demon from the freezing hell, a place, which is even feared by some demons. Only the strongest, mighties and most cruel demons can survive there. And these demons have an appetite for human flesh... The girl doesn't knows about this things at all, in fact she just found the book of demons, where a ritual for summouning a demon from the freezing hell is described and thought, it would be a bit fun to try it. So she is as surprised as the demon, as he is standing in front of her...
Well, why this came up in my mind while watching a tentacle film I don't even know myself, but it gives a clue, how the story could continue. :) If anyone would like to share this idea with me, I would be happy for an answer. ^^ Gender doesnt matter, but I would prefer to play the demon.