A hero of mine would have to be Perry Moore.
He was an interesting guy. He liked wine, surfing, new wave music, and writing on the beach in between or with the other three. He followed his dreams; he directed the Narnia movies and wrote a couple books, one of which was Hero.
He's a hero to me because he wrote that book, about a teenage superhero who happens to like guys. His heroic quality, both the character and the author, is helping people. Thom Creed heals, while Perry Moore wrote the book and therefore helped me through tough times in those awkward stages of growing up as a gay teen.
I noticed this quality in both the protagonist and the author as soon as I read the book. I received it on Christmas morning, and had it read before I went to sleep that night. The action to write it, and the actions Thom took with other characters, was helpful. It wasn't asking for anything in return.
If I had to assign that quality to my protagonist, I would make him very helpful. I wouldn't make him talk much, unless it was a verbal remedy. He would be the first to hold anyone if they needed it, or the first to step up if someone was in trouble. He might not be appreciated, but dammit he will help if he's able.