Volume 1: Red Like Your Blood

Four years have passed and the planet we call home no longer belongs to man-kind, but to the invaders, the vampires, who have killed more than two thirds of the human population. In what remains of a broken society, Toya Higioshi and his younger siblings have made a life within the Tokyo-Setagaya walls, along with the rest of the survivors who cling to the hope that the barrier between them and the outside world will keep them safe from their impending doom.

Like all the other men who survived in the region, the time has come for Toya to enlist as a soldier to help fight against the vampires who strive to capture humans as their livestock. There is one team in particular that his skill set has earned him a spot in, the one with the most dangerous job of all; gathering Intel inside the vampire fortress miles away on the other side of the walls. With the team's dwindling hope and fear that they will become nothing but food for their predators, the commanding officer sends a mysterious girl to join them on their mission. Because they are told only that she is the key to their success, it is not their hopes that raise, but suspicions.

Will Toya survive in this broken world? Will the team survive on their mission? Who is this mystery girl and why is she the key to their survival?