Ximena was a character who appeared in The Scorch Trials Official Graphic Novel Prelude, in the story "The True Maze." The graphic novel was intended to mesh with the film universe, and Ximena does not appear in any of the main books.
In the story, Ximena appears to be the teen leader of the other Icers (Group B). She treats Aris harshly when he arrives, first believing him to be a spy, then, after the other girls accept him as an Icer, gleefully punching him in the face because it was "the easiest way" for him to remember his name. Unfortunately, the very next day, Ximena is killed by a Shade while scaling an ice wall. The Icers mourn her and carve her likeness on a wall encircling their version of the Glade.
Ximena was the first girl to be sent into their Maze. She had brown skin and dark hair.