NSFS-040 Chisato Shoda, a mother who gives her body to her son after he sees her with the company president

Chisato Shoda lives with her son Satoshi in a transportation company dormitory after her husband dies. She works as a clerk, and the employees treat Satoshi like their own son. One day Satoshi sees his mother having sex with the president of the company, and from then on he sees her as a woman, not just a mother. He begins to pursue her, and she eventually forgives him and gives in.