19禁房事-不能说的秘密 19금 정사-말할 수 없는 비밀
导演: Park Bum-soo (박범수)
主演: Sunny-I (써니) / Yoon Ah (윤아) / Stew (찌게)
又名: 19岁的外遇-说不出的秘密 / Age 19 Rated Affair: A Secret That Can't Be Told
Two women start living with a man who lives alone.
The women introduce themselves as sisters looking for their long lost father and they start to seduce the man. Actually, these women are a serial killing duo who only target men who live alone. In the end, the man loses his life. While they are celebrating, a boy calling himself the man's brother, appears in front of them one day. He looks and sounds just like the man but has a completely different personality and he's nothing like the two women has ever seen before.