The man with the scarlet eye, aka "Friend", who may be The Devil himself, has been wandering the Earth in different guises, arranging and committing a multitude of massacres and other evil deeds. When Friend helps to arrange nuclear war, he ends up massacring a group of other survivors in his pursuit for the woman known as Sister and an item she carries to lead to the girl Swan. When Friend discovers Swan's power to bring life back to the dead Earth, he brings the information to a militia known as the Army of Excellence, leading to attacks on settlements and more death. It is revealed that Friend, annoyed with Swan offering him forgiveness, is attempting to help the now-insane former President of the US trigger a doomsday device to wipe out the world and the remainder of humanity while he watches, enjoys the show, and then dances on their graves.
"Lord" Alvin Mangrim is a homicidal psychopath with a love for decapitation and chaos. Escaping an insane asylum following the nuclear holocaust, Alvin leads his fellow inmates in a killing spree across the land, luring dozens of innocent men, women, and children to them to be tortured before carving their heads off with a chainsaw for Alvin to keep as trophies. Murdering Leona while trying to slaughter Swan and Josh, Alvin later butchers his way into a position at the AOE, where he assists the leadership in wiping out opposition and gleefully encourages the monstrous Friend's new leadership of the AOE into further villainy.
Ending Fatigue: The second half of the book starts to drag.
Nightmare Fuel: McCammon does not pull any punches with his descriptions of anything, including hacked-apart murder victims, the effects of radiation, and a lot of lingering on the smell of decay.
Paranoia Fuel: If flies didn't unsettle you before reading this book, they will by the time you're done.
Squick: Especially the descriptions about people who died in the explosion or were later murdered.
Diagnosed by the Audience: What exactly Tsukasa has is never touched upon, though he does at least seem to be a sociopath. Not that it stops him from being a great friend and Aroe's caretaker. Averted with Aroe, who is explicitly autistic.
Takuma becomes even worse. While his extreme actions could at first be considered justified because it was a matter of survival, he later starts killing and raping people just for the hell of it. In case you somehow missed the memo, the scene where he and his men gang rape Hibari and mutilate Tsukasa really drives it in.
