Bullfinch.

I do live with a cat, though she is probably the opposite of Oscar.  She has stubby deformed front legs from a birth defect.  Her front legs are about 3 inches long and her hind legs are full sized.  Yes she walks and runs on a slant, which, as you can guess, gives me no end of amusement.  She’s quite the conversation starter.  I found a cat on YouTube with some Oscar like qualities (courtesy of Carlisle from Steal This Comic, check the link on my site).  It’s pretty darn funny!