For the uninitiated to fanfiction terminology Mary Sue refers to a character who is so perfect and competent that it becomes absurd. I believe the name was given to a parody fiction written for the Trekkie universe -- ah and wikipedia confirms (https://en.wikipedia.org/wiki/Mary_Sue)

Also this gem, an excerpt from the fanfiction: "Gee, golly, gosh, gloriosky," thought Mary Sue as she stepped on the bridge of the Enterprise. "Here I am, the youngest lieutenant in the fleet - only fifteen and a half years old." Captain Kirk came up to her.

"Oh, Lieutenant, I love you madly. Will you come to bed with me?" "Captain! I am not that kind of girl!" "You're right, and I respect you for it. Here, take over the ship for a minute while I go get some coffee for us." Mr. Spock came onto the bridge. "What are you doing in the command seat, Lieutenant?" "The Captain told me to." "Flawlessly logical. I admire your mind."