You can post what ever. My current rule (official rules not made yet) is do not post anything that Southpark could not get away with.
South Park is on Comedy Central which is a cable service. Since you must pay for cable it does not fall under the Federal Communication Commission's jurisdiction of public airwaves like your local radio or NBC would. Technically, Comedy Central is legally allowed to air any material it wants, even pornography. (This obviously excludes any material that would be illegal to retain and/or view in your public home such as child pornography and/or snuff films.)
I can set an example as one of the VERY few times I've watched Southpark where I witnessed a transgendered Catholic science teacher engaged in multiple sex acts with an atheist science teacher. In this scene the Catholic said, and I quote, "Ram your hot manhood in my dirty monkey hole like the bitch I am." The scene was not a short one either.
While I have absolutely no problem with this kind of material I just wanted you to know where Southpark stands.
Hmm. Well. I haven't watched it since about the first or second season. Perhaps let's not go so far as that. I made a thread earlier asking for input on what the rules should be. I don't think I should be the one (at least not the only one) making the rules. So post your thoughts there.