@frenchfry with these stories it always seems best to think they make it up as they go along. In this case since he is the king's nephew you'd think Duke would be correct
Ayyy, a polite "go fuck yourself" is nice once in a while.
Ofc, these are only appropriate when the Villain has yet to do anything dastardly. When the Villain is going all out, politeness is frustrating
To my understanding the dad and the son can have different titles. The dad is the duke and the son has been titled baron. If and when he succeeds his dad he’ll then be known as a duke, dunno what will happen to his baron title. Could be like frenchfry says and he’d have them both.