What is RPF/RPS and why was it purged/banned from sites?
That’s fic about real people. First, it didn’t have a consistent name. Then, there were a few fandoms that were called by their fandom name. I think some people called it “actor fic” or something for a while. Then, finally, the term “Real Person Slash” was coined. Later, when it was more popular, it became clear that this slash-centric term would not work, and “Real Person Fic” became more common as a term.
Why was it banned? Well… because it squicks people, mostly. Partly, because people thought it was more legally dubious than fic about fictional characters. That’s probably not true in most jurisdictions, but people thought it was true.