Man, so many characters, it's hard to pick one. I guess that's what you get when you let about 50 ideas pile up in the back of your mind.
I'd have to go with James 'Jim Cognito' Cogson. He is an Englishman, living in Toronto, Ontario. His most distinguishing feature is the fact that his face is completely covered in bandages. He almost always wears a grey fedora, a grey and white striped dress shirt, a pair of jeans, and black dress shoes.
He changes the outfit and removes the bandages, however, whenever he takes a job; Jim Cognito is a master-of-disguise-for-hire. His face is surgically implanted with a layer of rubber, allowing him to alter his facial features on a whim. A special coolant he had created allows him to freeze his current facial appearance for 24 hours, during which he does his job. He guarantees all his acts will be finished within 24 hours or it's free. He's taken acting lessons and voice changing lessons for most of his life, allowing him to blend in whenever the need be, and be noticed when required.
James himself is a relatively quiet man, living out a normal life when not out doing 'jobs'. He reads the paper, he shops for groceries, he smokes the occasional Import A out behind the bar. Despite his bandaged appearance, he's always managed to stay inconspicuous due to his unimposing stature and manner of dress. He finds time, from time to time, to adopt a persona for his own benefit, and often adopts the persona 'Marlon Karlov' when, for his own enjoyment, he performs in local plays. He has adopted others, such as the time he had a whirlwind romance with a rich socialite as 'Harold S. Guttenburg', before 'Harold' mysteriously vanished in a freak yachting accident.
James himself does allow himself to be hired for assassinations, but only on the grounds that the person he is hired to kill is involved in some immoral acts, such as theft. His general view towards humanity is as an experiment by whatever force put them there. While not officially religious, he does believe in a higher power, though what that power is, he cannot say. He believes that by slaying those who attempt to avoid the darker side of human nature, even if they don't completely succeed, he will alter the results of the experiment in a bad way. By allowing himself to slay those who embrace the darker side, which he notices is getting larger, he hopes to keep the experiments balance. He does not, however, attempt to justify murder, or any of the other things he does, including theft, espionage, and sabotage.
James has never truly loved any woman, or anything for that manner, and regards no one as a 'friend', save one, a man named Albert whom works at a coffee shop not far from his penthouse apartment, whom James works through and receives his jobs. James is asexual, and feels no attraction to anyone.
Basically, that's James in a nutshell. Man, imagine if I went into detail.