In the future, the global earth warming has led to a rise of the water level and many districts vanished in the ocean. This story is about the 15 year old girl Mizuki Maiya, living in an ocean city. She has plans to become one of the bureaucratic elite members in the government of the ocean city. She should have such a bright future, but on the contrary to her desire to get a job in the government, she fails the employment test. Having lost her prospects, she decides to take up a job in the chain store of the all-round service company \"Nereisu Kamchatka\". It\'s just an ordinary summer in the ocean city. and the girls hold down a dangerous job---