[Ch. 13] A character describes in detail the lead-up and aftermath of being assaulted in high school. They refuse to describe the assault itself - but the passage is still quite unnerving.
[Ch. 13] A character recounts in great detail the leadup and aftermath of being assaulted. They refuse to state what type of assault. [In general] Multiple rape jokes and SA references. A possessed character considers assaulting a woman but doesn't get the chance. Another sequence where a character worries they may have raped someone during a patch of missing memories, though this turns out to be untrue and the possible-victim is entirely fine.
A major character was bullied and abused (most likely sexually) by several classmates in high school, which teachers deliberately ignored. While the worst of it is only brought up in Chapter 13, it is referenced by other characters throughout the book.
Not on screen. A character commits suicide prior to the events of the book, and another is (in his words) "put on suicide watch" towards the end but does not attempt it.
Frequent bug-based body horror. Descriptions of humans, including children, having internal organs harvested while still alive or being painfully transformed into other things.
No jokes, though the narrator is overweight and very occasionally makes self-conscious remarks. There's also brief story of an overweight child being bullied to an extreme degree in high school.
Putting aside the "person starts seeing monsters and thinks they're losing their mind" aspects expected of the genre, two main characters were made to attend a behavior disorder youth program in high school. Years later, both are still treated with disdain and called the r-word, and conversations about the program contain descriptions of the orderlies injuring students.
Dave's mental health is not the best, with PTSD-induced anger issues and violent blackouts. He spends a good chunk of the book worried about hurting others, and at one point beats up an asshole without remembering it. His other violent outbursts are the result of either self-defense, possession, or supernatural weirdness.
Ehhh...? One chapter includes an argument between the protagonist and his girlfriend during a pregnancy scare. She doesn't want to keep it, but he's worried the fetus's ghost will literally actually physically haunt them. While the girlfriend is not actually pregnant, the argument does trigger their breakup and might be uncomfortable to read.
The police frequently break procedure. While this helps the protagonists as often as it hinders them, the narrator is very uneasy at how rights are ignored.
Used for shock comedy. The antagonists frequently cause the protagonists to hallucinate racist, antisemitic, and homophobic broadcasts, which are printed in full and with all the eloquence of an edgy 13-year old. Frequent use of slurs. A black character recalls a time they were assaulted due to their race.
Supernatural entities are capable of "haunting minds", causing hallucinations and blackouts. There are times that the point-of-view character - and by extension, the audience - are manipulated into believing he's committed sexual assault or worse.
One of the themes of the book. The narrator was abused in high school, and blinded a bully in self-defense. Years later he struggles with anger issues and violent impulses, but ultimately avoids becoming his greatest fear.
Dave, the narrator, never knew his father and was ultimately put into foster care after his mother was committed. His adoptive family also moved away without him when he graduated high school, though he is apparently on good terms with them. Both incidents are discussed periodically throughout the book.
[Ch. 13] A character describes at length being held down by classmates in high school and being assaulted. He refuses to elaborate on what kind of assault. [In general] Multiple accounts of people being restrained.
If someone gets in a car, they're probably not getting out of it until it's been knocked off the road. A major character is also a car crash survivor, and recalls the experience of watching the other passengers die in gruesome detail.
A discussion on abortions, with a character being against them because he's convinced that will get the couple haunted by a baby ghost. (Not metaphorically.) Ultimately, no-one turns out to be pregnant.
A teenager overdoses on painkillers prior to the events of the book. Several characters die from overuse of a fictional, supernatural drug, though instead of the usual symptoms of overdose, they explode.
An exorcism is at one point mistaken for a seizure. John also fakes one multiple times throughout the book but given he yells "SEIZURE! I'M HAVING A SEIZURE!" while doing so, it's not terribly convincing.
Both main characters are arrested and brought in for questioning by the police. One is strangled by a police officer while the other "dies" during questioning.
John Doesn't Die at the End, if that's what you're here for. Nor do Amy, Jennifer, or Molly. Most other named characters die. I have no idea how to answer that question succinctly for Dave, and neither do the characters.
A copy of molly explodes after eating a Testa-Mint.