Charles isn't what one would refer to as a happy camper. More often then not he is dragged along on crazy adventues against his will and deals with more than most ponies will ever encounter. Odd by unicorn standards, he tries(unsuccessfully) to keep out of the affairs of strangers, but somehow ends up being dragged along from one end of Equestria to another more frequently than he would like. Also, he refuses to discuss anything about his cutie mark.

Charles © Brony.org
artwork by  afterthefox

MLP: FiM © Lauren Faust/Hasbro