Each person's sexual history is going to be different. Crowded parties, candlelight dinners, and top bunks are some of the many different experiences people have. Some partners you might have known for years, some for hours. But when it comes to sex under the influence, the potential risks put everyone on common ground. After drinking, it becomes easier to dance, easier to introduce yourself to people you don't know, to talk, and to laugh.
Inhibitions break down and magically everyone seems more available with a buzz on.
The reason it becomes easier is that alcohol helps you to forget about the things that usually make you nervous. Alcohol frees you up by making everything seem OK, and it helps you get your nerve up. We all know that, ideally, the best way to avoid these problems is to have a relationship with a person where all of these questions and fears have been dealt with through honest talk and mutual interest. But the idea of sex comes up in less than comfortable situations as well. It comes up when you meet someone at the party, at the bar, or wherever.