The function of a quasi contract is to impose a legal obligation on a party who purposely failed to fulfill an express promise.

Quasi Contract

A legal principle that allows a court to award compensation for goods or services rendered where there was no actual contract, based on the concept that it would be unjust to allow one party to benefit at the other's expense without payment.

Legal Obligation

A duty enforced by law that requires a person or entity to act or refrain from acting in a certain way.