Leviathan manga volume 3 features story and art by Shiro Kuroi.

Monster or human … What sleeps deep in the darkness?

Alliances form among the trapped students inside Leviathan's ruins—victims against bullies, boys against girls, rich against poor—each confront each other in a deadly struggle to be the sole survivor.

Kazuma has found refuge with the group that controls the cafeteria, but doubt creeps into his mind… what if the charismatic Yo is not as selfless as he seems to be? He quickly finds himself orchestrating the expulsion of this leader, hoping to takes his place. Will Kazuma be the single champion to reach the cryogenic chamber before the others, or is his diminishing sanity leading him more simply to self-destruction and demise?