Upon awakening in a hospital ward, Shiki Toono discovers that he possesses the extraordinary ability to view invisible lines that make up all matter in Shingetsutan. Should these lines be severed, the object is immediately destroyed. Though he opts to keep this gift secret, Shiki's tranquility is shortly disrupted when he encounters a peculiar woman with vivid crimson eyes on his way home from school. In a sudden psychotic outburst, he appears to kill her before passing out. Matters worsen when he is attacked by demonic hounds the following day, but is unexpectedly rescued by the same woman he had thought he killed. This woman introduces herself as Arcueid Brunestud, a noble vampire. To get to the bottom of their ancestral roots and the wave of murders that have descended upon their town, Shiki and Arcueid join forces to embark on a journey together.