The well planned discovery leading to the whole-hearted adoption of one's fantasy? - Ah to dream! Of course the ease with which this occurs is also part of the fantasy. In the real world, there is another person to consider. They will also have their own fantasies and preferences. To ignore this is at best rude. But what if the other person says that they don't have fantasies, and they are quite willing to go along with yours? A dream come true? Don't you believe it.
They say, 'never look a gift horse in the mouth'. Well, look. And look hard. Small sacrifices early on become huge rifts later. I speak from bitter experience, here. I found it very suspicious when my partner told me she didn't have fantasies. The relationship ended, because I didn't question this more.
Take your time. Ask questions. It's easy for a girl to find out what turns her guy on. We come with a protruding barometer, for heaven's sake! Finding out about her can be a little more tricky. She has to be honest with herself, before she can be honest with you.
While you figure out how you're going to figure this out, here's a little light fantasy to pass the time...