Yes. :> Basically, the difference between "mature" and "explicit" IS that PG13/18+ line.
Something that would fall under the "mature" guidelines would be a thread that is very sensual, with references to and posts leading up to sex, but perhaps fading to black or otherwise OOC'ly ending the thread prior to the act itself actually occurring. Or, perhaps your character is thinking about a past act of violence in great detail, or thinking about torturing another character (in detail, again) to shut them up.
If it's just a passing reference to these things, like a paragraph in a post -- then you wouldn't have to mark them mature. However, if a central idea of the thread is one of the mature subjects, your character thinks about the mature subjects in great detail, or the thread is otherwise very heavy in elements that are PG13 but not quite R-rated, then they should be marked as such. :>
Explicit threads would be ones where your characters actually engage in a sexual or violent act and the act itself is described in great detail. Anything where the questionable/mature act is actually and actively occurring (even through writing techniques such as flashback) must be marked explicit.
If you're curious about a certain situation, it's better to just mark it mature and ask about it. If it's not, we can always just remove the mature warnings. X3 Thank you very much for being cautious and marking your threads, too!
