Hour of the Zombie Vol. 7 (manga)
The tenuous peace between human and zombie is threatened, and everything looks poised to return to slaughter and death. Umezawa hungers for vengeance. Yet Houjou tells Akira of a bombshell discovery: slowly, the amount of time the zombies can regain their senses is actually increasing. If enough days go by, the zombie outbreak might fade away completely! But how many corpses will be created before that day comes…?