Checkers'll give the dirtiest glare when thwarted... ears back, sneer on his little kitty face. But he doesn't hold grudges... He'll be wild for ten minutes, flaunting his ability to do all the things he's not supposed to--run across the dinner table, swipe at the dog's nose, and so forth--and then he'll be back for a petting and a purr.

If he gets physically injured by someone (stepped on, hit by a door, etc.) he knows it was a mistake and will come sniff your finger and make up with you. He forgives easily.