Natsuko, who was left behind by her husband, is a single mother raising one child. She devotes herself to work and housework so that her child will not lack anything, and lives a life where her own things are secondary. Her son also successfully entered a high school and is quite popular in his class, which makes her mother relieved. When her proud son asked if it was okay to have a friend stay over, Natsuko said OK without hesitation... She never imagined that this would be the reason she herself would be fucked by her son's friend and become obsessed with dicks...