Ratings:
PG = Fine for anyone to join
PG-13 = Some violence, a little romance, slight bit of language
R = Lots of violence, romance, and language
IO = Invitation only becase it is graphic enough to have to be pre approved by all individuals included.

Also please write if the thread is OPEN (open for others to join uninvited)
or CLOSED (invitation only)

So a basic thread here should look like this:
(name of thread)/PG/open