Due to her husband's unemployment, Mikan begins working as a housekeeper for the Kaneko family to support her household. While working, she accidentally witnesses the homeowner's younger brother, Ryuji, with an abnormally hard erection. Flustered, she becomes the target of his sexual harassment and is forced to give him a blowjob. Experiencing a cock harder than any she's ever known, Mikan becomes addicted to the sensation. From then on, she actively seeks out the rock-hard erections of the men living in or visiting the house, taking each one into her mouth as she chases after that intense pleasure.