A new monitoring project has been born with the full cooperation of a certain bedrock bath facility in Tokyo! Can you cuckold a regular couple who are enjoying a bedrock bath without the girlfriend finding out? At first, she is confused and embarrassed, but she is excited by the thrill she has never experienced before! She muffles her voice so that her girlfriend next to her doesn't find out, saying, "Ah! I'm going to come..." Her body is covered in sweat, her pussy is dripping wet, and she can't hold back any longer as she inserts it raw! Slowly with a slow piston... it feels so good that she ends up doing it more violently...! "Oh no! Oh no! She's going to find out!"