Gribouille's girth

Take a look at this cat, I love him to bits, but he's bigger than me. First I thought it was because I'm small but I'm starting to realize that actually this is one big cat. Toulouse, by comparison, is a fraction of Gribouille's size. While Toulouse may be annoying when he pounces on your toes at least he moves, Gribouille sleeps and rarely does anything else. He looks skeptically at those of us who dare to get in his face. And when he does move he causes environmental disruption. Seriously, when he strolls in front of the window during the afternoon he causes a lunar eclipse.
Papa has tried putting Gribouille on diet food but that failed. I've tried tugging his ears and pulling his hair to get him mobile but he just glares at me. The Garfield, "I'm just big boned", routine only goes so far, perhaps Gribouille needs to be introduced to Jenny Craig.