The handful of times I've had to describe FeralHeart, I described it as a free-roam chat/roleplay game, where you can use either a feline or canine model(and however you can customize it) to interact with other people.
A few times I've had people ask if this was really something I should be playing, since(to them) it seemed more like a place for kids... which I then proceeded to tell them just how many people I know on here who are legal adults, as well as pointing out the sheer number of professional-grade artists who obviously also enjoy FH. Besides, there's nothing wrong with having a casual conversation with someone younger than you!