How about a dragon how cheerfully rules over a kingdom; his people all know him for what he is, and dragons are looked upon as wise and benevolent creatures. Dragonslayers from other kingdoms coming to free it from 'tyranny' are likely to get beaten to death by peasants with cast iron skillets.
Someone needs the blood of a dragon, given willingly, to make a rare potion. Guess who gets hired to sweet-talk a dragon into giving up some highly powerful blood?
There is a person who has a well-known reputation, probably involving something illegal. But this person is either very clever and crafty, or really like his or her privacy, for no one knows who this person actually is. As an added twist, perhaps this person is of an age that would noramlly be wildly inappropriate (say, a child is a much-feared bandit) or maybe not the expected gender or even race.