A furry is someone that identifies with anthropomorphic animal characters (or sometimes just animal characteristics). No dressing up required. Now, a lot of the people that go to cons tend to have more money, so you will see more fursuits and such, but most furries do not dress up.
TIL. I first heard of furries like 10 years ago and hadn’t ever known this. I thought the entire thing was dressing up.
I used to as well until I looked into it, which is why I now know way, way more than anyone really needs to (there is… a lot.) Anyway, figured I’d explain just in case. You didn’t seem like you had bad intentions, so thanks for being understanding.