'Wot' in Britain is a lower-class term, most often seen in the caption to a 'Chad' - a stylised cartoon of a face looking over a wall, with the caption 'Wot, no X?' where X could be any commodity. It originated in the 1940's as a comment on wartime shortages, and is still sometimes seen. The spelling suggests a Cockney pronunciation of 'what'. Adding 'What?' to the end of a sentence is a British upper-class affectation, and I'd have thought unrelated. How it got into a Calvin and Hobbes strip I don't know. Andrew