Dr. Claw showed great affection for MAD Cat, stroking the sinister feline often. This became a trademark of his on the show (other than his "hands" shtick, though the two are often indistinguishable). However, Dr. Claw was also sometimes an abusive pet owner, and would bully MAD Cat when he perceived the feline as annoying. In an episode that took place in the first season, Dr. Claw was depicted laughing over a triumph, and MAD Cat, in typical "copycat" manner, laughed along with him. Dr. Claw then demanded what the cat was laughing about, adding furiously, "I did all the work!" An episode or two later, Dr. Claw was engaged in tongue-lashing his minions. MAD Cat did the same. Dr. Claw again abused the cat and angrily growled out that he was that one who gave the orders. Sometimes MAD Cat didn't have to do anything at all to inspire punishment, and Dr. Claw's maltreatment was almost casual or even unnoticed and reckless on some level. In more than one episode Dr. Claw would simply slam down his fist, not caring where the cat was in his anger or if his pet would escape in time. (However, in one episode, MAD Cat was ready for him and glued his fist to the desk) Dr. Claw once broke MAD Cat's Inspector Gadget toy bank after Gadget foiled one of Dr. Claw's plots, and MAD Cat cried uncontrollably. In another, he simply caressed the feline's head until it hurt, with MAD Cat's expression betraying discomfort. MAD Cat always forgave Dr. Claw (often by the next scene).
MAD Cat seems to understand English well: in Launch Time, MAD Cat takes instructions from Dr. Claw and operates the controls of the Mad Jet (firing a missile). It is unknown if MAD Cat is male or female.