Mary Mahajan was created by Ryan North and Erica Henderson. She made her first appearance in The Unbeatable Squirrel Girl #2.
Her last name was provided for the first time in issue 39 so that, as the narrator at the bottom of the page says, "she is not only a more well-developed character, but now also not completely impossible to look up online!"
Major Story Arcs
Mary has helped Squirrel Girl in several adventures, from Dr. Doom to, most recently, a Skrull impersonating Tony Stark.
Squirrel Girl considers Mary to be a very capable computer engineer (Doreen knows Mary as a fellow CS student at Empire State University) with a Chaotic Neutral personality. Mary is known to be interested in a variety of outré weapons.
Mary has been dating Chipmunk Hunk.
Powers and Abilities
Mary has no powers but is a skilled computer engineer.