What term fits this definition a cunning or evil person?

There are many words that could fit this definition, depending on the specific nuance you're looking for. Here are a few options, ranging from general to more specific:

General:

* Devious

* Machiavellian

* Sly

* Cunning

* Scheming

* Treacherous

* Wicked

* Vicious

* Malicious

More specific:

* Scoundrel - A dishonest or unprincipled person, especially a man.

* Rogue - A dishonest or unprincipled person.

* Villain - A person who is evil or wicked.

* Monster - A person who is cruel or inhuman.

* Psychopath - A person with a personality disorder characterized by a lack of empathy and remorse, often accompanied by criminal behavior.

* Sociopath - A person with a personality disorder characterized by antisocial behavior and a lack of empathy.

The best word for your specific context depends on the particular traits of the person you are describing.