Natsumi divorced her husband and started living in an old house with her only daughter Kyoko. However, a few days after moving in, the bathtub in the house breaks down. It's summer, and Natsumi and Kyoko feel uncomfortable with their sticky bodies, so they head to the ``female-only public bath Senmeyu'' given to them by a newspaper deliveryman, but... However, for some reason, Natsumi is sent to a ``Shirayuri'' who is different from Kyoko at Senmeyu. There, Natsumi meets Natsuko. At that time, Natsumi had no way of knowing that ``Shirayuri'' was a ``hot spring exclusively for lesbians.''