The Toyama sisters miss the right moment to hide in a mixed bath sauna (Pixiv Fanbox)

There is a summary zip at the bottom of the page that includes an extra pubic hair differential.

The Toyama sisters (Kasumi and Asuka) had no idea that this sauna was a mixed bath.

The sudden appearance of a male visitor made them realize that it was a mixed bath.

Since it was a sudden happening, neither of them could cover their hands.

They decided to act calmly.