What is a good site that I can create a RP for my site...?

I am looking for a website that I can make a private role play for a website that I already have and it's members. It needs to be able to allow us to do any genre that we want (we understand rules such as no profanity, cursing etc thats not an issue) and that certain members can join but only them and I. If anyone knows of something at least along some of this stuff, please please please let me know asap.