Hushed exchanges among the female student populace of Shinyo Academy center around an enigmatic supernatural entity. This entity is Boogiepop, a Shinigami who is rumored to murder people at the height of their beauty before their allure wanes. Few know of his true nature: a guardian who, between periods of dormancy, manifests as the alter ego of a high school girl named Touka Miyashita to fend off "the enemies of the world." Now, a string of mysterious disappearances—presumed by the school to be merely runaways—has caused Boogiepop to awaken. But somewhere in the academy, a menacing creature hides, waiting for its opportune moment to strike.

Boogiepop wa Warawanai subtly explores the intrinsic associations between human beings and their perception of time, while delving into its characters' complex relationships, emotions, memories, and pasts.