After God. Volume 1: Sumi Eno

Thirty years after the gods reduced Tokyo to rubble, survivors set out to answer a seemingly impossible question—how do you kill a god?
Japan has been invaded by gods—and they’ve left nothing but death and destruction in their wake. With entire cities now classified as uninhabitable danger zones, Anti-God researcher Sachiyuki Tokinaga is determined to find a way to take down the gods and save humanity. When chance leads him to high schooler Waka Kamikura, the two may just end up changing the fate of the world forever.
Desperate for answers about her friend’s disappearance, Waka breaches the Tokyo danger zone in search of clues. Instead, she finds Tokinaga, a researcher with the Anti-God Scientific Research Institute. While Waka tries to decide if she should trust Tokinaga, he quickly realizes Waka is hiding a dangerous secret of her own—one that may just be the key to killing off the gods once and for all.