dA groups are a circle of people that share the same interests, like if you look at the Homestuffed one. Just a bunch of people that like fat homestucks, etc. RP is done like.. this:
Coldheart snorted, and slammed a paw down on the dusty earth. "Obviously not. Our leader has gone mad!"
See? It's pretty much book style, most of the time. Here, any four-legged animals are accepted. Anything else you'd like to know?