It doesn't matter whether you're an avid reader or writer of fan fiction because when you come to Adult-FanFiction.org, you'll have plenty to see. This place has an active community as well as story archives, resources to help you craft your own adult story, and contests.
When it comes to reading, this site has a large and high-quality archive of various stories divided into sections such as anime, books, Buffy, cartoons, celebrity, comics, final fantasy, games, InuYasha, LoTR, manga, Naruto, television, celebrity, YuGiOh, but also non-English works, and original works. Moreover, each of these sections has a few or more categories to further help you with your search. If you're more into writing, then this site has a member tools section where most of the items on the drop-down list lead you to the Adult-FanFiction forums and include things like adopt a story or (writing) challenges and requests. The forum also has reviews, guides, and sections for collaborations, as well as character development, and a drawn art sub-forum with lots of content, that's unfortunately only available if you're a registered member.
Navigation on the site is good although you might be overwhelmed with all the different sections and forum subsections when you first come here. Luckily there are only a few ads, but the site owners ask for donations each month ($350 total). The forum has an advanced search, while the site has a member directory and member search. Moreover, the forums seem active, and they also offer an instant chat feature for registered members.
Adult-FanFiction.org is a bit crowded and confusing at first, but this place has a large and varied archive of adult fan fiction stories, as well as lots of resources and guides for writers underpinned by an active forum and community, so it's well worth visiting.