Unkind thoughts
It is suggested that the Twits are so ugly because they have unkind thoughts. Indeed, Roald Dahl writes that "A person who has good thoughts cannot ever be ugly. You can have a wonky nose and a crooked mouth and a double chin and stick-out teeth, but if you have good thoughts it will shine out of your face like sunbeams and you will always look lovely."
Revenge
Revenge is a key theme of this novel, as it tells the story of the birds and monkeys who have been mistreated by the Twits and seek revenge against them. However, we also see revenge take place within their marriage, the Twits often play tricks on one another.
