The only son, Nobuo, who grew up between a married couple who had reached a period of boredom, was starving for his mother's love but was unable to interact with him well. One day, through a prank played by a friend, Nobuo comes to know about the hair that has grown gently on his mother's armpit. This transforms his mother into a sexual object, and Nobuo, unable to suppress his growing desire, forces her down... Nobuo's rapidly distorting feelings for his mother lead him to commit even more obscene and humiliating acts...