S is the registered owner of a 500-square meter land. His friend, B, who has long been interested in the property, succeeded in persuading S to sell it to him. On June 2, 2012, they agreed on the purchase price of P600,000 and that S would give B up to June 30, 2012 within which to raise the amount. B, in a light tone usual between them, said that they should seal their agreement through a case of Jack Daniels Black and P5,000 "pulutan" money which he immediately handed to S and which the latter accepted. The friends then sat down and drank the first bottle from the case of bourbon. On June 15, 2013, S learned of another buyer, C, who was offering P800,000 in ready cash for the land. When C confirmed that he could pay in cash as soon as S could get the documentation ready, S decided to withdraw his offer to B, hoping to just explain matters to his friend. B, however, objected when the withdrawal was communicated to him, taking the position that they have a firm and binding agreement that S cannot simply walk away from because he has an option to buy that is duly supported by a duly accepted valuable consideration. Does B have a cause of action against S? Who has the better right? Explain the rules on Double Sale.