Most every character is available right now. It's in the DLS vein of RPs, which means you have to observe the rules carefully (DLS = Dirty Little Secret) to make sure you respect others, but other than that you can have fun creating quirks for your favorite (or not so favorite) characters. ^_^ AU from just before episode 25, although at least knowledge of events past episode 25 is encouraged, as there will be spoilers.
Apply and have fun. ^_^