OK, I must jump on the band wagon here! I, too, have black cats. And yes, they are box and bag freaks! My youngest kitty always has her sniffer into everything. She once squeezed herself into my purse to retrieve a gum wrapper! (How she knew it was in there is beyond my human level of knowledge!) They also seem to have an extreme urge to get into my clothes drawers (while they are closed!) The best thing about my black cats is their face ... so black that the only thing I can see is their eyes.