Rinko works part-time as an office clerk. She has a plain impression and even the younger employees don't pay her any attention. Even at home, her husband doesn't pay her any attention. Masturbation is what fills her with the loneliness she feels. Rinko has a stronger sexual desire than most people. One day, at a bar where she went drinking with a colleague, she heard a young man say, "If you give me 30,000 yen, I'll sleep with a mature woman." Even though Rinko was thought of as a suspicious old lady, she exchanged contact information with him. And they actually met. Desperately suppressing her tension and excitement, she clutched the brown envelope containing 30,000 yen...