He's the "moderator" of the household. If I yell at the cat, Koodge is on it by running up to the cat and barking. He does mouth the cat, but hasn't bit him. Thank goodness. I think he's just trying to tell him what to do but there is a language barrier! Haha. Koodge hasn't ever been fond of young puppies, so I imagine the cat annoys him pretty good.