The only club devoted to rats as pets. Rat lovers can find the American Fancy Rat & Mouse Association. Southern (German Fancy Rat Society Berlin). Welcome to the National Fancy Rat Society website. a group of enthusiasts intent on promoting the rat both as a pet and an exhibition animal. National Fancy Rat Society. likes · 13 talking about this. The National Fancy Rat Society is a UK society which promotes the rat both as a pet and.