It varies from person to person. I know this because when I'm with my best friends, we talk about this sometimes. We all have varying notions of what is romantic.
But basically, I think being romantic boils down to a few things, doing something that is special in some way, a little something out of the ordinary. It honestly doesn't have to be amazingly unique, and for some people the cliche candlelit dinner may be the way to go.
Thoughtfulness in most any way is romantic, and can be a major factor on the romance level. Also, a recurring thing in what a lot of people have said on what they think is romantic, is spending time alone together, or having fun in a public place, but not going with anyone else along save the two of them.
But that's just what I've noticed. As everyone has completely different notions of what is "romantic". One of my friends thinks going on a camping and hiking trip with her boyfriend is romantic. Sounds like hell to me. <p>
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Happy Halloween, you bastards!</div></p>