en Cuevana 3. "Tachibana Yusen" in a certain town. There is a public bath that Kasuko, who has extraordinary big breasts, inherited from her father. There are regular customers from my father's time, but young people and old people gathered for Kasuko's big breasts. However, it was decided to open a sports gym with a spa in the neighborhood, and as a countermeasure, he was considering new services with regular customers.