Lieutenant Colonel Maes Hughes (マース・ヒューズ) is a character in the anime/manga series Fullmetal Alchemist (a.k.a. Hagane no Renkinjutsushi [鋼の錬金術師]). It follows the adventures of two young alchemists who want to restore their bodies, after a failed attempt to revive their dead mother completely destroyed one brother's body and partially destroyed the other's. But this site isn't about them, now is it?
Hughes is, obviously, a member of the military (originally a Major, but he received a promotion), but he manages to avoid battle by having a desk job in the investigation department. That doesn't mean he can't kick ass when he needs to, though. But even though he's a member of the military, his loyalty truly belongs to his friend and superior Roy, and he acts as a source of support in Roy's climb to the top.
While he supports Roy, Hughes in turn is supported by Warrant Officer Falman and Sheska. He torments Sheska ceaselessly, making huge demands on her ability to remember anything she's read, but she still works hard, because she, like everyone else, knows that Hughes is a great guy, and he cares deeply about everyone in his crazy way.
But when you think of Hughes, you don't think of his job, you think of his family. The most important thing in the world to him is his wife and daughter, and his love for them borders on obsessive! He's such a great father, other people should learn from his shining example! *cough* Hohenheim..
As for his age, I've heard he's 31, which seems about right. I just haven't been able to find any mention of it, even now that he's finally mentioned in the list of characters on the official site.
On a more technical note, his seiyuu (voice actor) is Fujiwara Keiji, and a more inclusive list of his various roles than I am willing to type can be found here.