In Whitten v. Greeley-Shaw 520 A.2d 1307 (Me. 1987) two people were having an affair.  The mistress had the guy sign an 'agreement' in which he agreed to give her a monthly stipend and some other prizes.  The agreement required nothing from the mistress save not calling the guy at home.  Later he loaned her money for a house.  When she stopped paying off the loan, the guy foreclosed on the house.  The mistress argued that this was part of the 'agreement', but the guy successfully argued that since the agreement did not require her to do anything, there was no consideration and therefore it was legally unenforceable as a contract.