Stuart is a young adult human male of less-than-average height, slightly overweight. He has brown hair around bottom-of-nose length, with no fringe, which occasionally falls across his face. He is often seen in a battered brown leather bomber jacket and jeans.
Depending on the setting, Stu is usually seen with guns: a pair of pistols or a firearm (perhaps a reference to his author's injokeish Silver Shotgun, but Stu's is always a normal machine without notable powers). In his Xceptional-Men incarnation (see below), Stu's superpower is a subtle one without destructive capability but with the potential to be used in creative ways.
Stu is notable for being a deliberate self-insertion, occasionally used as an authorial mouthpiece. He is frequently used to inject a voice of common sense (usually ignored) into the proceedings, and to highlight what the author considers weaknesses or illogic in the source material. Owing to the gentleness of his parodic style, Stu is often overruled by other characters, who usually succeed in their own way while staying faithful to the genre.
The very name Stu deliberately signifies the male version of a [Mary Sue]? character (the "Gary Stu" or "Marty Stu"). Despite this, Stu was intended from the outset to be as far as possible from the Mary Sue archetype: thus, he has no extraordinary abilities beyond other characters in his genre, and stories do not revolve around him. He is never the viewpoint character.
Stu is unusual in that he has no tragic past and is upbeat and polite to everyone whenever he can.