Tuxedo isn't a breed. It's a coat pattern: a bicolor cat, usually black and white, with a white chest that looks like a shirtfront and often white paws, chin or a facial blaze. Grey-and-white tuxedos exist too. The pattern comes from white spotting in the KIT gene, and because it isn't sex-linked, males and females are about equally common.
Most tuxedos are domestic shorthairs, usually 6 to 14 pounds, and many live 12 to 18 years, so adopting one is a long commitment. Stories about tuxedos being smarter or bolder are fun but unproven, because color doesn't set personality. In St. Charles, that means meeting the cat in front of you and asking whether its age, energy and coat suit your home, from a small apartment to a house with a yard.