Those whose cause, object or purpose is contrary to law, morals, good customs, public order or public policy;
A and B entered into a contract of lease of the latter's house for P10,000 per month. The purpose of said lease is to serve the same as a sex den or prostitution house. Knowing this intention, they proceeded with the deal.
NOTE: The contract is therefore void from the beginning because the cause or consideration is contrary to law and morals.