The topic I'd like to start with is how small, familiar details can make a character real to the audience. My take on eroticism is heavier on the romance angle than the erotic. Since reading is a very mental activity, the usual pornographic imagery isn't enough to thrill the reader; their mind has to have a firm grasp (heheheh) on who exactly these people are and what they are feeling. Who cares if he's a hot immortal or she's a transforming cyborg? I have to know why the sexual encounter is important to them in order to live the moment with them.
Something that Stephen King described in his absolutely fantastic book On Writing is that it's not the number of details you include that make for a great description, but the quality of a few choice details. I think this is especially important in sci-fi/fantasy, since so much of the story may be wildly outside the normal sphere of experience. Our transforming cyborg starts out as a very distant, amorphous entity; then she does something familiar, like chewing on her nails, or being unable to sleep after reading a scary story, and she becomes a little less distant, a little more familiar. Knowing the color, fabric, make and cut of a man's clothes may or may not tell me much about him, but simply stating something like 'his wardrobe cost more than his education' or 'his clothes were the mismatched affair of one who has few choices, if any at all' tells the reader far more about the personality, values and state of life of the character in question. Enough of those little details add up to create in the reader's mind a clear picture of the character - and along with it, a connection to said character that makes the reader care who they bed, and how, and why, which makes it especially relevant to erotic stories.
I'd like to hear your thoughts and ideas on the concept. Share with me little details you remember that stuck with you, whether you wrote them or someone else wrote them. Disagree with me, and tell me why. Agree with me, and sing my praises. (Ok, it's true, I like that option the best.) Think about it and tell me why you think it is or isn't true, and how it does or does not specifically relate to erotica and the sci-fi/fantasy genre. Thank you!