Places for authors to go to talk about their writing with other authors exist, a form of support and assistance, like discuss_writing, fictionwriters, and writers_guild.
Such writing communities don't take writing of a sexual nature as seriously as other forms of fiction. This community is for the discussion of writing erotica or smut stories. A supportive journal for brainstorming, story ideas, assisting with writing blocks or word choice.
For the most part this community is not meant to post your finished stories at. Other communities, such as adultsexstories, get_ur_rocksoff, and sexstories exist for this purpose. Posting rough drafts, or sections of your story you're looking to flesh out is a little more acceptable.
1) No personal attacks.
2) Reduce the level of negative comments. If someone posts some topic that offends you (rape, beastiality) please opt to not read the post, and choose to not comment with negative, discouraging comments over the subject matter. Critique, constructive critique is acceptable, posting to show your displeasure with the topic isn't. If you have nothing useful or positive to say, say nothing at all.
3) If you post a topic/story/etc that could be construed as controversial, list what the subject matter is at the top, to avoid someone mistaking a relatively "safe" post as something more hardcore.
4) If you are posting a story, segment of a story, or a long post, please exercise an lj-cut. Here is instructions on how to use an lj-cut.
5) Using images isn't encouraged, but if you do, please put it behind an lj-cut.