Drama unfolds as an ex of Ruki's claims that her five year old son is his. This comes at a time when he and his new wife Vaila Leigh-Matsumoto are trying for a child of their own. All they want, is to spend time alone, like they do everytime he finishes with something big at work. But Sakura refuses to make it easy and shows up at their beach house in Osaka. Neither Ruki or Vaila knowing how she got the address. Vaila takes matters into her own hands, when she remembers something about Ruki's family, that will tell them definitively, whether little Katsu is Ruki's or not. Something, that is almost as good as the DNA test that Sakura is refusing to have done.