Koztah is the sort to speak his mind and stand up for what is right, though he does have the know how and physical power to back it up. He is psychic, using those skills in battle for his own gain - which makes him a fairly lethal mercenary. Being Dragonborn means that he doesn't really fit in with dragon society. The dragons don't really want him, and there are some of other races who aren't too keen on his existence either.
Preferring to be on his own, and used to things being that way, he has bounced around from town to town as a wayward vagabond.