A woman who wears revealing clothing, or no clothing at all is not a slut. Whether she is "slutty" (meaning has the attributes of a slut) depends on the opinions and customs of the observer, and those opinions and customs vary wildly from person to person. There is no common ground.

The really disturbing thing, though, is that being a slut (sexually promiscuous) is considered a bad thing. Anyone in this thread, or in real life, who has ever looked at someone and said to themselves, "She is such a slut. She should be ashamed!" is contributing to a pervasive social problem that really needs to be corrected. There is nothing morally wrong or evil about having sex, or even choosing multiple partners. There IS something morally wrong and evil about using a person's sex life as grounds to decide that they are inferior or disgraceful.

Regardless, we have no idea what Rowena's sex life is like. She doesn't seem to have a spouse or partner. We DO know that she is a ridiculously successful businesswoman, and like many other admirable women in the game she commands respect and authority. She's one of the few NPCs to change outfits at all, and she wears what she damn well pleases. Anyone who takes issue with how she chooses to dress can take their business elsewhere - except, no, they can't, as she's pretty much running a monopoly. :P

All that said, to play devil's advocate, Rowena is a fictional character. She doesn't choose how she dresses. Her CREATORS choose how she dresses. Whether it is really the case or not, there's a pervasive belief in the video game industry that most gamers are male, video gaming is a male hobby, and that games should cater to male interests first, and to females' interests later, or never. With that, it could be argued that Rowena's (and certain other females') outfits are chosen to INVOKE an image of "sluttiness" to appeal to male gamers and encourage them to keep playing.

Whether you believe that is the case here is totally up to you. Just realize that, whether you are male or female yourself, looking down on a woman for what she chooses to wear or who she chooses to sleep with makes YOU guilty of poor morality, not the woman. They are her decisions to make, not yours, not society's.