(one's) better nature noun phrase
Used to indicate the best aspects of one's character, especially one's generosity, magnanimity, mercy, or empathy.
Although Aunt May complains a lot, I've seen her better nature shine through -she always comforts me when I am sad.
Used to describe someone who is good at persuading people to do or believe something
Show fortitude, and determination of character
It means people cannot change their nature like personalities, habits, etc.
A despicable person who does unscrupulous or immoral things
Someone is not as bad, cruel, maleficent as they are said or believed to be.
Bad people but they are still rich or wealthy.
Fairy tales have a lot of the devil looks after his own but in the end they are still punished.