Sexual Desires: Influenced by Media?

I've been pondering the basis of human desires and how they are related to or effected by the media or material we read. Are we born with the chemical makeup that provides us with certain sexual needs and desires, or are they easily influenced by what we read and watch? For instance, we had this whole "Twilight" obsession and a fascination for vampires. Did this craze push me toward my "biting" fetish, or was I seeking out comfort in these movies/books because I already had these desires within me and wanted to explore them further? The same question arises when we examine my sexual orientation/preference. Does watching "The L Word" make me want to explore my options with women, or was the reason I was dying to get home every day to finish Season 6 (which, btw, left me totally unsatisfied in the end) because it was relatable? Having the sexual orientation that I do, which I often refer to as "I don't discriminate", but others refer to as "bi-sexual", I often prefer men over women, or vice versa, depending on my current mood. I also notice that I tend to read more novels involving man-woman relationships or woman-woman relationships depending on this current mood. And the same goes for movies, etc. So I wonder if I seek out specific leisure activities based on my current sexual desires, or if those books and movies guide the gender in which I'm currently most attracted to. It's like the old chicken and egg debacle: which came first? So the question remains; which came first: my desire or the force that drives it?