At the helm of the Kurokawa Group, Japan's largest amusement company, is the president, Akira Kurokawa, who sets a condition for his nine daughters to inherit: they must bring the most outstanding "son-in-law." And the most outstanding son-in-law? The one with the strongest penchant for "play." Ninth daughter, Claire Kurokawa, teams up with the formidable gambler, Sou Shirahagi, pretending him to be her husband, as they embark on a high-stakes gamble that could determine their entire lives!