Mason

Mason is Sig Curtis' assistant at his meat shop in Dublith, a town located in the center of the southern region of the country. He is also acquainted with the Elric brothers.

Personality
Not much is known about Mason because he does not appear very often, but he is obviously caring and hardworking. The one instance that defines his character was when he cooked fish over a fire for the Elric brothers before they starved.

His Part in the Story
During the Elric brothers’ training on the island, Mason dressed up as the man in the mask to keep them alive and help them train. Usually good humored, upbeat, and easy going, he appears to have a close relationship with the Elrics, as he immediately recognized and greeted them upon their return to Dublith. While his duties mainly revolve around caring for the Curtis' meat shop, he also performs other tasks to aid Izumi and the Elrics whenever needed. He helped to gather information for Izumi on Al's whereabouts when he was kidnapped, showing that he has affection for the boys. While not battling the brothers during their training, he helped to secretly care for them and keep them alive, as well as giving them hints on understanding more about the basics of alchemy.

Mason has also displayed a fair degree of martial arts prowess and strength, particularly when wielding a club, as well as exceptional survival abilities during his time during the Elric brothers' training, possibly due to living with Izumi and Sig. It is also apparent that he is aware of Izumi's condition and the background behind her ability to transmute without a transmutation circle, as he quickly and forcibly changes the subject when Ed and Al ask why Izumi has no children.

Trivia

 * All of Mason's initial appearances are cut from the 2009 anime, though his role is still the same. Unlike the manga, he has very little screentime and the fact that he is the Masked Man ends up omitted entirely from the adaptation.
 * Curiously, he appears in the cover of volume 6 from the Fullmetal Alchemist (manga).