两个风情女子和一个单身狗同居的故事。

《19禁房事：不能说的秘密》讲的是两个女人开始和一个独自生活的男人生活在一起。女人们将自己介绍为姐妹，寻找他们失散多年的父亲，并开始勾引这个男人。 事实上，这些女性是一对连环杀手，只针对一个人生活的男人。 最后，男人失去了生命。 当他们庆祝时，有一天，一个自称为男人的兄弟的男孩出现在他们面前。 他的外表和听起来就像那个男人一样，但是却有着完全不同的个性，他不像以前见过的两个女人。

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 mans brother, appears in front of them one day. He looks and sounds just like the man but has a completely different personality and hes nothing like the two women has ever seen before.