There has to be a balance struck between allowing creative expression of authors as well as making the forum a safe and comfortable zone for younger and sensitive audiences so that no one is offended.
One suggestion I have is the fanfiction ratings system that has been adapted by fanfiction.net. Fiction Ratings Site Similar ratings are used in other fan fiction sites too.
The author of the post is responsible to rate their fiction. Preferably this is done in the subject of the post, so that the ratings are visible to everybody. Make all authors follow a standard subject line format for their threads for ease of reading and sorting by readers.
A story subject line would look like this
Name of Story [Rated:K9+ Ch:19 Pg:184 Updated:03/31/08]
K5+ is stories suitable for all ages. K9+ is geared for people 9 and up. T13+ is for teenagers and older. M16+ may contain material like mild violence, kissing, brief bedroom scene etc that may be inappropriate or offensive for some audiences. M18+ means the content has explicit violence or sex.
Since a site has to be registered with fiction ratings, the admins of this site can register India forums or adopt a rating system like the TV, film or video game system. Like G is for all, PG13 is for teenagers and older. R is for seventeen and older with mild violence/sex while M is explicit content with graphic violence and sex.
Since this forum has young audiences the admins can choose to prohibit M rated fiction. There usually is debate over when content crosses the line of R and becomes M. It usually depends on the reading community, some or tolerant, some are liberal - as a writer understand your readers, the community you post in and use rational judgment. Always use ratings, and err on the side of caution and warn if a chapter may contain some inappropriate material. Moderators ensure ratings are followed and no one publishes stuff that is prohibited and be fair to writers when making decisions. Writers who want to continue writing graphic content or find their content deemed inappropriate need not fret, be open to editing your content. Also there are many blog services and free web hosting services to post your creativity with uncensored unedited content. You can privately contact your frequent readers to inform them where they can obtain uncensored and unedited content.
Happy Reading and Writing!