Young and beautiful mother Haruki and her son Shiro appear to be a couple to outsiders. However, even with such a close parent-child relationship, topics related to "sex" are always difficult to discuss. Unexpectedly, Shiro brings pornographic films to school, which is discovered by his homeroom teacher, who then calls Haruki to the school for a discussion. To resolve Shiro's problem, Haruki decides to use her own body to educate him...