At the request of his sister-in-law, salaryman Jintaek finds himself living with his twenty-two year old niece. She bears an uncanny resemblance to her alluring mother, and as Jintaek takes care of Eunji while maintaining his disciplined life, he becomes ensnared by desires he didn’t know he had. To make matters worse, his niece introduces him to other people as her ‘dad’. But an even bigger problem arises… Every night, she comes to him with a request. “Dad, I want to do it with you.”