I wonder if imgflip will approve this oh god

I'm not one, but I actually looked this up a few days ago, so I'll tell. It's essentially an anthropomorphic animal fandom, animals that stand on their hind legs and have human qualities, like clothes and personality. That's pretty much it. You can apparently get an entire costume. Fan art, stuff like that, from what I know. So, yea, the fandom itself is probably close to your second definition. Not a bunch of perverted 60 year olds(sorry this was long).

and the costumes are all blue and colorful. also not furry btw.