In the near-future Japan, global warming has brought the large city Yokohama underwater, and only the hills remain above the ocean surface. What used to be one of the largest cities in Japan now feels like a small town. Basically, the existence of the island country itself has been threatened. However, there is no feeling of desperation, devastation, nor hopelessness. People are enjoying laid-back lives, and they seem to appreciate each other's company, enjoying the quiet and peaceful time together. This is especially so with Alpha, a carefree young woman who runs a cafe, named Cafe Alpha. She