My mom's cat is extremely obese, not quite this big though. He isn't overfed, he's just extremely lazy. He's been put on several diets, to no avail. He just won't lose weight. During one of his diets, the vet gave my mom special food for him, and instead of eating it, he refused and bullied my little dogs to get to their food instead. He was banned from their food bowls, but it still didn't help.