
Our world is actually falling apart, unbeknownst to most. A bizarre apparatus hiding in the depths of Ueno's Shinobazu Pond, a giant snail clinging onto the Eiffel Tower, a demon lord in the form of a beautiful girl... these and countless other cryptic entities—called "Ends"—are driving us closer to the apocalypse. However, some youngsters decided to reject that fate and secretly took up arms. They are fighting, not to stop the countdown or to eradicate the threats, but only to delay the inevitable. Why would they choose such a thorny path on their own volition? To make the most out of their youth in this godforsaken world! I, a former cartel slave (and ESPer), have had a pretty shit life so far, to be honest. But maybe here I'll be able to lead a fulfilling school life, at least? (Source: Kadokawa, translated)
Kochira, Shuumatsu Teitai Iinkai. is a Japanese novel of 747,746 characters, with 18,965 unique words and 2,464 different kanji. Its difficulty rating on Jiten is hard, 3.2 out of 5. The full vocabulary list ranks all 18,965 words by how often they appear, and you can study them on Jiten or download them as an Anki deck.
Here are some of the words that appear most often in this media, as well as a sample of its rarer vocabulary.