Of course we all come here to feed our individual demons, and they can have very specific appetites.
Good way to clarify things.
A lot of the preferred characteristics of a story, mentioned here so far, apply of course to any kind of story : good plot, characters worked out, accuracy,…
Windar’s core question was, what elements make a story ‘erotic’ (to which particularly his third question applies).
We are discussing here the specific niche story genre, this forum is about. Jon Smithie points out well that it is about ‘feeding our own demon inside’. A story, besides being well worked out and well written, is experienced as erotic, when that demon is satisfied. That’s, I guess, different for each of us. People who write stories, like me, do it for the pleasure of setting up a plausible story, but also to satisfy the demon. When reading one, the demon looks over our shoulder, and his appreciation of the erotic level, is my appreciation.
One thought is, that ‘erotic’, is perhaps a too narrow focus. ‘Excitement” (of which the erotic is a substantial part, of course) seems to cover it more, to my opinion. To go back to Windar”s opening posting : what’s erotic? A naked girl on a cross’. Sure it is! But the whole via cruxis, including interrogation, whipping, stripping, public humiliation, raising the cross,… that’s the excitement that gives the erotic aspect a big added value! According to my demon inside! Just also remember that vanilla people, who have not the luck of having a demon like us, may be erotically interested in the view of a naked woman in a crucifixion pose, but not at get excited by the via cruxis aspect, and even find it very repulsive and disgusting, as they cannot discern between the fantasy and the grim reality of an execution. They only see cruelty, think we are cruel sadist people, even a danger for society, and cannot grab that our exciting fetish is about erotization of death (and my demon agrees with that).
For me, this has a strange effect on storywriting. I put time, research and energy to write a plot, a story, a character development, on its way to downfall. But when I get so far, my writing blocks, since there show up many ways to make it end, all exciting ones, I often write them out in four versions, and then, I still cannot choose, since ‘my demon’ finds them all exciting.
About the consensual aspect in this kind of stories, I often think back to my schooldays lessons about the Ancient Greek tragedy writers (Aeschylos, Euripides and Sophocles), who made their characters go down either by fate, or by their own acts, or a combination of both. I think, this still works as a base of a good plot, particularly in stories like ours. No one walks deliberately to the cross.