Oh darnit.... I was just about to make a theme featuring someone of the other gender... ^^
Oni, I totally see you as a cheetah with an eye-thingy and that hat. When you first changed to that avatar, I immediately thought "that's him, that's his real him". Not kidding! So, I guess you got me where you wanted ^^
Unlike just everybody before me, I don't tend to associate people with their themes. Well, perhaps with people I don't really know, and people with really n00bish usernames and so on. But people I see regularly, I actually do look on their usernames. For example, i don't imagine DC as his current theme.... heh. So I instead get really really confused when people change their names drastically.
I did however imagine Beachy as Roxas for a while^^ (don't tell him I said that)
Myself, I'm probably one of those who change themes at least once a week. But I hope I've got a username unique enough for people to recognize me anyway ^^*