A Mary Sue is a type of fictional character, usually a young woman, who is portrayed as unrealistically free of weaknesses. Originating in fan fiction, a Mary Sue is often an author's idealized self-insertion. Mary Sue stories are often written by adolescent authors.The term Mary Sue was coined by Paula Smith in the 1973 parody short story "A Trekkie's Tale", as the name of a character standing in for idealized female characters widespread in Star Trek fan fiction. A male character with similar traits may be labeled a Gary Stu or Marty Stu.