Spring break, an interval of time between the second and third year of high school.
Koyomi Araragi encounters a blood-chillingly beautiful woman. The iron-blooded, hot-blooded, cold-blooded Vampire, she calls herself "Kiss-shot Acerola-orion Heart-under-blade."

On the brink of death after losing her four limbs, she asks Koyomi to save her. After experiencing fear, chaos, and finally conflict, Koyomi gives his own blood in order to save her.
But when he awakens, he finds himself re-born as her vampire kin.

Koyomi wishes to revert to being a human from a vampire. However, he must take back all of Kiss-shot's limbs to do so. Working as a negotiator, Meme Oshino stands in middle ground as Koyomi attempts to recapture her four limbs by challenging three powerful vampire hunters.

This hellish spring break, the final one of his high school life, is only just beginning.