On the surface, Saya is a stunning 16-year-old, but that youthful exterior hides the tormented soul of a 400-year-old "halfling". Born to a human father and a vampire mother, she has for centuries been a loner obsessed with using her samurai skills to rid the world of vampires, all the while knowing that she herself can survive only on blood like those she hunts.

A maths teacher acquires the power to travel into movies to save the woman of his dreams and bring her back to her correct film.