You don't even need to label yourself as a villain. My character could more or less fit into the 'good guy' archetype, except he's got such hatred for Ishgardians due to past events that he'd gladly see every one of them dead and their cities burnt to the ground (and he may or may not be plotting some domestic terrorism towards those ends).
That said, only one person knows about his feelings towards Ishgard and everyone else he's encountered would be hard pressed to think of him as anything more than a somewhat abrasive know-it-all. To the outside world he's no different from any other adventurer, even though behind the scenes he may be working towards more nefarious ends.
And even then the act would be completely justified in his (possibly damaged) mind, so he doesn't see himself as a villain at all.
That said, only one person knows about his feelings towards Ishgard and everyone else he's encountered would be hard pressed to think of him as anything more than a somewhat abrasive know-it-all. To the outside world he's no different from any other adventurer, even though behind the scenes he may be working towards more nefarious ends.
And even then the act would be completely justified in his (possibly damaged) mind, so he doesn't see himself as a villain at all.