Sentence:  Short of actual <WSD>actorfics</WSD> (which don't seem to have reared their ugly heads mychsic recently), now & in the past, most references I've noticed tend to be harmless humouroussic little injokes in which, say, M or S discovers an old magazine in which the other appears in an embarassingsic photo identical to one of DD or GA's. 
Meaning of the word marked with <WSD> tags:  A fanfic focusing on the imagined activities of a real actor or actors.