The sad story of Sayoko and Santa's past comes to light as Sayoko embarks on a massive necromantic attack in an attempt to take vengeance on the world that treated her and Santa with such injustice. Zombies threaten to wipe out humanity and wit the majority of the UQ team beaten, it is up to Santa to make a difficult decisions. Will he oppose his only real friend and save the world, or will he allow all the scumbags who wronged him to die the deaths they might deserve?

First published in Japan in 2015 by Kodansha LTD., Tokyo. This book reads from right to left.