The end of the world has come: moral decay, grayness, hunger, filth, disorder, and madness. The heroine understands the sinister nature of the human heart and the hardships of the world. She knows how much she weighs and protects herself carefully. She does not have a Virgin heart, and of course she has not become black. She just uses a pair of eyes that look mature but are actually frightened to avoid risks, until she meets the male protagonist, and she goes through ups and downs with him, experiencing the baptism of the apocalypse.