Although Kana feels at peace with her earnest but indifferent husband, she also feels bored. One day, her brother-in-law Tetsuo comes to visit the house... Kana rejects Tetsuo's advances as he is a playboy, but he keeps coming on to her and they end up having a relationship. His caresses know different pressure points than her husband's, and his thrusts penetrate deep into her vagina, bringing her to orgasm over and over again... Kana is stunned by the pleasure she has never experienced before. However, feeling guilty for betraying her husband, she continues to reject Tetsuo's repeated advances...