Sex Girl 2: Elementary school friends Min-soo, Woo-hyeon and Ji-yeong are close friends who still hang out with each other even if they're now older. Min-soo likes Ji-yeong but he knows that his best friend, Woo-hyeon, likes Ji-yeong too. He is hesitating to confess. One day, Min-soo who happened to spend the night with Ji-yeong was happy that he told Woo-hyeon that he was going to sleep with Ji-yeong as if nothing happened, and Ji-yeong also thought nothing about it. The story of three young people agonizing between strong friendship and love is just beginning.