The most annoying creatures that have bothered me so far in Oblivion are the imperial guards who turn out to be the owners of the horses I am trying to steal, or at least ride away unnoticed...but these guys always show up and usually fine me and haul me off the the Imperial Prison to pay. But the last guy just gave me a choice of surrender or resist arrest - so I resisted and then had so much trouble backing up the horse away from the building that he wound up killing me. So I jsut didn't have to save that fiasco.
