Yu, exhausted from housework, is suffering from severe back pain. One day, her husband's friend comes to their home. The man works as a dispatched masseur and immediately notices Yu's back pain, which even her husband had failed to notice. He suggests giving her a massage, saying that it would be serious if she damages her back. Feeling guilty for not noticing her pain, her husband also encourages her to accept the treatment. However, the man had been targeting Yu. As he touches her in sensitive areas, her pleasure intensifies, and she ends up accepting him...
