I am currently planning a short story, but I hit a major snag right off. My main character has to be semi-anonymous. By this I mean, other characters around him know some things about him, but not his past, or his motivation, and his enemies don't know anything at all about him. I have this personality strong in my head, but I just can't give it a name or appearance. I know that it is a man of average physique, slightly muscular. Any ideas?