Enextase had a niche market for this and has some of the best stories on this site, IMO. My girlfriend's rival, making a devil out of me, etc.
My own Trapped in Amber was my stab at the genre, although I tweaked the formula.
A lot of succubus stories have this theme as well. The Succubus Summoning series in erotic horror, for instance.
Last edited by Ironiclaconic : 02-19-2013 at 05:18 PM.