I took everybody's advice and did not read the Twilight books, but my curiosity about the phenomenon got the better of me, so yesterday I watched the (first) movie.
Oh.My.God. it was bad. Luckily, I found it literally laugh-out-loud bad, rather than just annoying bad. Here is the movie: Bella, a shy, pretty girl, moves to small town in Washington state. She speaks only in monosyllables and generally looks surly or nauseous, but everybody immediately loves her, and she acquires a group of nice, funny friends. All the boys in her group of friends ask her to prom, and she acts irritated and says no. This does not upset the group dynamic, and instead the boys ask the other girls in the friend group. Bella goes prom dress shopping with the girls but makes it clear she is uninterested in their whole silly prom thing. She really only wanted to go so she could buy a book about Native American myths, because ...
Edward is a pale, cute boy who acts like he is going to vomit when Bella's in his vicinity. She stares back, also looking like she's going to throw up. They do not flirt; instead they act angry at each other. He does stuff like follow her around all the time, save her life repeatedly from various perils but act pissy about it, and have very cold fingers. She does some detective work using the aforementioned book, as follows: she opens it to a random page, reads one caption ("The Cold One"), then Googles that, and discovers--Edward's a vampire! She confronts him--angrily, nauseously--and he angrily and nauseously admits that he IS a vampire. Further, for several months he's been sneaking into her bedroom at night to watch her sleep, and he has a very strong urge to kill her because her hair (or her blood? unclear) smells delicious.
Now--ta da!--they're totally in love!
Uh oh, now another vampire wants to follow Bella around and has a strong urge to kill her, but this is not OK because Bella is already Edward's special tasty ladyfriend. Then more peril for Bella ensues, Edward saves her again, and Bella and Edward go to prom. Ta da!
I may spend the rest of my leisure period rewatching Buffy, to get Twilight out of my system.