Yuka Shima (Mayu Matsuoka) works as an OL at a large general trading company. Suddenly, she is transferred from her office to an aquarium that is affiliated with her company. She now works as a keeper at the aquarium and her senior is Kaji (Kenta Kiritani). Yuka Shima struggles with her new job and marine animals, but with her bright personality she is able to grow as an aquarium keeper.