Akane, Shiraishi, and Eki go to the same school and additionally participate in the physics club. Akane is the oldest, she is the head of the club, Shiraishi is the smartest, and Eki is the most unpredictable and believes in the occult. One day Eki had a prophetic dream in which a plane crashed and a ship sank. And then she wondered why planes fly and ships don't sink at all. It turns out that the science that can answer these and other questions is called hydrodynamics (or fluid mechanics), and Eki with Akane asked Shiraishi to tell them about it. Together with our characters, we will take a fascinating journey into the world of fluids and learn many new and interesting things about their properties and laws which they obey and which we use in everyday life without even realizing it. (Source: DMK Press, translated)