Kim Sam-Soon is an overweight, 30 year-old unemployed pastry chef whose boyfriend callously dumps her on Christmas Eve. As Sam-Soon creates an enormous scene at the hotel restaurant, it is witnessed by Hyun Jin-hun, the very cocky owner of a fashionable Seoul restaurant. By some a stroke of fate, Sam-Soon finds herself making a deal with Jin-hun that if both of them have a secret contract relationship, Jin Hun will pay for the extreme 50 million won debt Sam-Soon's family has amassed. Despite the contract nature of their relationship, the two begin to have feelings for each other but when Jin-hun's ex-girlfriend suddenly returns from the United States, a romantic tug-of-war ensues.