The obsession many tween, teen, and even young adult girls have or have had with Edward, the sparkly vampire with teen angst, is scary (all of this applies equally to Jacob, the fluffy werewolf with abs). However, I think it goes deep. For many girls, I believe, this isn't just some superficial teeny-bopper phenomenon. It comes from desires that are core to human nature and are heavily influence by the entirety of their lives. I believe that the obsession many girls have with Edward Cullen is actually the result of an incorrectly pursued desire for Jesus Christ, and this is why.
Jesus Christ is the Son of God. He is supernatural and divine, yet so human. He is mysterious and relatable. You can know Him intimately and still know so little of Him. He has so much power and holiness and even wrath, but He gives love freely to us. He is so completely dangerous, but so completely good.
We were designed for Jesus. He is the one humans were meant to be in relationship with. Therefore His qualities attract us in part, even if our sin can hold us from Him. Because of this, we are so often willing to settle for cheap imitation, someone who has qualities like this but devoid of His fullness and glory. Compare, then, a description of Edward Cullen.
Edward Cullen is a vampire. He is supernatural and immortal, yet can be so human. He is mysterious and relatable. You could know him intimately and still know so little of him. He has so much power and beauty and even wrath, but he can fall in love. He is so completely dangerous, but still so good.
If you couldn't tell, these descriptions were close to identical, because Edward Cullen embodies the Jesus that fallen humanity would rather have. We don't want a holy God who will judge sin, so we take all the traits of God that we do like and put them, albeit far less powerfully, in a person of our own imagination. Then we give him our love and devotion. When this happens, it has become idolatry. Now, there are obviously many fans of our vampire friend who do not treat him as an idol, but the point is Edward all but begs to be worshiped He is a fallen man's imagination of what Jesus should be like, and this draws so many in. We were made for Jesus, and characters like Edward are ideal candidates for trying to fill that gap in those who do not know Christ.
Again, before anyone yells, not everyone sees or feels about Edward this way. Sometimes they're just superficial teeny-boppers. Sometimes they just like the story and the character. These things aren't wrong. So don't crucify me. (Or impale me with a wooden stake. Or cut me up and burn me.)