Mary Sue

A Mary Sue (sometimes just Sue), in fanfiction, is a fictional character with overly idealized and hackneyed mannerisms, lacking noteworthy flaws, and primarily functioning as a wish-fulfillment fantasy for the author or reader. Perhaps the single underlying feature of all characters described as "Mary Sues" is that they are too ostentatious for the audience's taste, or that the author seems to favor the character too highly. The author may seem to push how exceptional and wonderful the "Mary Sue" character is on his or her audience, sometimes leading the audience to dislike or even resent the character fairly quickly; such a character could be described as an "author's pet".