Experience
I can't write from experience because I have never had sex but I can believe that is a beautiful thing. What I have experienced is the result.
Sex can be looked at in three different ways, something that is sexually attractive, a way to escape this world, and feel the best, or it can be a beautiful thing that gives you the best, or it can be both.
No matter what way you look at it, sex is human, it is not a sin, it is a gift from God, Himself, and it allows us to make the most precious thing. It gives us life. Even if nothing comes from the beauty of sex it is still beautiful. Even if you don't have kids you are still experiencing the nature of it. It gives us the best feeling we have.
Again, I don't know what sex is like, I have heard of it, I know how it works, I believe it's good, and I want it, but I don't know. I am guessing what makes sex so good is that it is an experience, almost like nothing ever before. The only way to know is to do.
But if sex is a beautiful thing it shouldn't be done in the wrong way, otherwise it is misused. Use it when the time is right when you're married, and then you will know more than I do.