When I write fiction, I make sure to exclude as many details as possible. Obscurity breeds the opportunity for the reader's imagination to roam. You may know the character's name. I may release the information that he or she is considered to be attractive. But who am I to define what's beautiful? Speaking for myself, I prefer to paint my own personal picture.
Have you ever watched a movie based off a book you've read?
Only to be grossed out by the actor playing your favorite character?
Furthermore, when writing erotica; I try not to elaborate too far on the action. Who am I to describe the indescribable neural signals that results from sex? When that warm, wet sensation envelopes; who can fully depict the sparks shooting up our spines? When it comes to sex and sensuality; it is truly "different strokes for different folks". Why write about their eye contact during oral, when some people hate that? Why go on and on about his fist full of blonde hair, when some people prefer brunettes or Afros?
In my book, the best art is open to interpretation.