Maria Ross (マリア・ロス, Maria Rosu) is the partner of Denny Brosh. Both are introduced when they are assigned to protect Edward Elric, who she develops a maternal affection for. In the anime, Ross later appears in the rebellion against King Bradley, saving various characters from execution. In the manga she is framed by the homunculi for the death of Maes Hughes. Roy Mustang stages a prison break and then fakes her death, giving her a chance to flee to Xing. Though she has asked that her family and Denny Brosh not be told that she is alive so as to keep the secret from getting out, she has pledged to come to Mustang's aid if ever he has need of her and has done so in a crucial situation, eventually doing so in chapter 89.

Source: Wikipedia