The original cat obviously found a cloning machine while he was away. Maybe it was a ploy to get double his meals, but I don't think he thought it through.
HAH! Makes sense Frank, Mr. Meow on the right looks a little chunky monkey. A little double dipping going on there I'd say.
I read somewhere that cats know how to open portals into parallel universes. Sort of like the book "The Man In The High Castle", except if humans meet their double, they vaporize or something. Apparently cats can handle that situation better. Maybe the cat from the other parallel universe had an owner who didn't feed him well. He's looking for a better one.