From the first day, human life has been subject to some social principles and these principles are also the guarantor of human social development. Among these principles, the principle of marriage is very important for the beginning of family life and is also very important for the survival of human race. This principle has been adopted in different ways in different civilizations since ancient times. In addition, it is also emphasized in almost all religions. But in modern times, a so-called enlightened class has not only rejected religious and social rules like marriage for family life, but has also found an alternative to it, whereby men and women live together having a sexual relationship without being married. This theory is known as Cohabitation or Live-in Relationship. Since the beginning of cohabitation in 1960, this ideology has taken hold of various countries and in the present time, it has also appeared in Islamic countries on the name of liberalism. Apart from this, the process of cohabitation has many disadvantages, including physical and mental diseases and psychological problems, and many people in western countries are suffering from these problems. Therefore, if the way of cohabitation is not stopped now, it is possible that the people of Pakistan will also suffer from these problems in the future. This article will explore the dangers and harms of cohabitation while discussing its socio-ethic and psychological impulses in society along with recommendations for avoiding tis lifestyle.