Studies suggest that the degree of alcoholic intoxication directly correlates with the level of risky behavior. The same, she says, holds true for casual sex. There are many ideas as to why people think young adults are involved in this hook up culture, such as that they feel like they have to do it to fit in. In each case, the relationship's dominance in the lives of those involved is being voluntarily limited, and there is usually a sense that the relationship is intended to endure only so long as both parties wish it to. From Wikipedia, the free encyclopedia. Hooking up generally refers to having sex; however, many others indicated that when they say hooking up they are referring to something less than intercourse.