When a couple went to a mixed-gender hot spring, they unexpectedly encountered a beautiful, bisexual woman! When they first met, she was touched on the buttocks, which confused her a little, but she couldn't say anything. After that, when they went to the mixed-gender hot spring together, the woman from before came and made them speechless with her techniques, and it developed into a threesome led by the beautiful, bisexual woman! What will happen to the couple who have both been cuckolded in body and Kokoro...?