If I have NO employment contract or NO Non-compete contract can I still be sued?

I live in SC however my employer is in NJ - I have never signed an employment contract, agreement and have never signed a non-compete. If I start a business in the same industry however not directly competing with my employer, can I be in jeopardy of a law suit? If I do start the other business while still employed with my employer in off hours, can I be in jeopardy? In NJ if I have NEVER signed any contract and NEVER signed any non-compete, I can still be sued for Breach of Duty of Loyalty - One key restriction imposed by the duty of loyalty in NJ and NY is that even if you have not signed a non-compete agreement you probably cannot work for a business that competes with your current employer until after your employment relationship ends. Does this law or restriction apply in SC?