(Synopsis from the back cover):
«With the battle between the Monarchs and the Rulers quickly approaching, Jinwoo must rally the international community against this oncoming threat! Though he wields unimaginable power, he’s acutely aware that he can’t fight them all on his own...but will the other hunters stand with him?»
The amount of lore revealed in this volume is immense, so I'll be careful not to give away any spoilers. It's quite rewarding.
It's very subtly hinted that two characters "sleep" together without being married. There's no explicit content, but it's dropped in, as if it were nothing.
Explicit and brutal violence, gore. The sheer amount of sadistic violence is chilling.
The idea that after death there is nothing, only a void, and that one returns to nothingness, to non-existence, is repeated once again. This raises many questions because the idea doesn't hold up on its own (besides generating existential despair and anguish). And, faced with imminent death, the characters wonder if they have lived a good life. Or, for example, a quote: "He closed his eyes, convinced that he would never open them again."
Jinwoo breaks his promise (or his lax ethical code) and uses Shadow Extraction on the souls of humans killed in battle. But at least he asks their permission to use them in battle.
The novel presents a capricious god who is bored and creates creatures merely for his own amusement. He is neither benevolent, nor invincible, nor all-powerful. Furthermore, why are some beings presented as "Immortal" while it is repeatedly stated that after death mortal creatures return to the void? What is this injustice?
There is a (failed) suicide attempt born of despair. It is somewhat pessimistic and fatalistic.