“Duress exists where one, by the unlawful act of another, is induced to make a contract or perform or forego some act under circumstances which deprive him of the exercise of free will.” Radford v. Keith, 160 N.C.App. 41, 43-44, 584 S.E.2d 815, 817 (2003). A threatened act is unlawful “if made with the corrupt intent to coerce a transaction grossly unfair to the victim and not related to the subject of such proceedings.”