Soo-jeong, who works at a design office, is in a great mood these days as she is recently married and entered a sweet honeymoon period. She expected everything to be perfect, but living with her younger female cousin has left her with an odd, uneasy feeling. One day, the cousin sneaks into the master bedroom, and while Soo-jeong is sound asleep, she engages in an intimate sexual act with her brother-in-law.