After his father remarries, a young working man begins living with his new mother and his adult college-student stepsister Suzu. Close in age but still awkward around each other, they are suddenly left alone when their parents leave for a honeymoon. A typhoon knocks out the power, and Suzu clings to him in the darkness, quickly closing the gap between his stern, distant personality and her outgoing, affectionate nature. Spoiled by her full-body embrace and huge breasts, he loses control as the balance of power reverses and he drowns in her sweet tongue kisses and tight leg-locking hold.