Welcome to RPG,
@copper!
I've never read the Warrior Cats series but I always had the curiosity since some old friends were really big on it but I don't think they ever roleplayed it, they'd just go under some of the character's names a lot in our IRC rooms.
If you'd ever like to do a roleplay with me on animals -- especially cats! -- let me know! I've always wanted to try that so hopefully, I can get the mechanics of playing a cat right.
Have a good one!