Bella and Edward didn't have sex until after they got married because of Edward's old-fashioned ways (the guy's been around since 1901, after all). Plus he was worried he'd crush her to death in the heat of the moment. (Again, with the romance.)

The deal was to turn Bella into a vampire after she tied the knot, but they hold off a bit so she can experience her wedding night without the distraction of unquenchable bloodthirst.

After Edward swept Bella away to a family-owned island for their honeymoon, the sex "Twilight" fans devoured three books and three movies for finally happens. Bella's bruised, but satisfied ... and also pregnant.

Through some technicalities that were never covered in our sex education class, Bella and Edward made a hybrid baby, which means the part-vampire fetus slowly kills her from the inside. In what some have read as an anti-abortion plotline, Bella insists on keeping her baby against the wishes of loved ones, including Edward. The majority of "Breaking Dawn -- Part I" chronicles Bella's torturous pregnancy, which demands that she drink a steady diet of blood .... even before she actually becomes a vampire.

OK, you're caught up now

Giving birth to a vampire/human child is a spine-breaking horror show, one so gory that Edward had no choice but to turn Bella into a vampire to save her.

But before they can be a happy, mostly vampire family with their new baby Renesmee -- who ages at a much faster rate than a human child -- the threat of the Volturi rises once again.

And that's where we pick things up in "Breaking Dawn -- Part 2." The last installment has not only promised us an epic battle and a twist ending, but Bella finding out about Jacob's "imprinting," when he becomes uncontrollably attached to baby Renesmee on sight and completely devoted to her for life.

Like we said -- it gets complicated.