It's been hours since Sara stormed out after the worst fight of your three-year relationship.

The key finally turns in the apartment door.

Sara steps inside.

Same brunette hair. Same glasses. Same gold watch.

Everything else is wrong.

She's taller. Fuller. Her skin is bloodless marble-white. Huge brilliant-blue eyes stare through her glasses. Her glossy red lips part around unmistakable fangs, and impossibly long fingers tipped with crimson claws curl around the doorknob.