When an agreement is discovered to be void, or when a contract becomes void, any person who has received any advantage under such agreement or contract is bound to restore it, or to make compensation for it, to the person from whom he received it.
Illustrations
(a) A pays B 1,000 rupees in consideration of B's promising to marry C, A's daughter. C is dead at the time of the promise. The agreement is void, but B must repay A the 1,000 rupees.
(b) A contracts with B to deliver to him 250 maunds of rice before the first of May. A delivers 130 maunds only before that day, and none after. B retains the 130 maunds after the first of May. He is bound to pay A for them.
(c) A, a singer, contracts with B, the manager of a theatre, to sing at his theatre for two nights in every week during the next two months, and B engages to pay her a hundred rupees for each night's performance. On the sixth night, A wilfully absents herself. With the assent of B, A sings on the seventh night. B has signified his acquiescence in the continuance of the contract, and A is entitled to be paid for the seventh night.