The spirit each person is believed to have in attendance, according to certain religious or mythological traditions, which tries to negatively influence him, and is opposed by his good genius; loosely, someone who is a bad influence.
An intellectually brilliant person who excells at using his or her mental abilities for negative or harmful ends; especially a criminal mastermind .
A tutelary angel watching over a particular person in monotheistic contexts.
A person who watches over another.