Warning: Spoilers ahoy!
- Serge may spend most of his page time being a quirky, likable guy with a strong sense of justice, but for all of the ingenuity, Black Comedy, or cathartic karma that go into most of his kills, they can get pretty disturbing. Any interaction with the seemingly harmless Serge has the potential to end with someone bound and gagged, as Serge either describes in agonizing detail what's about to happen to them or lulls them into a false sense of feeling like they can survive before subjecting them to a fight for their lives that may be Unwinnable by Design.
- Wrongdoers who Serge isn't even particularly angry at and/or that are pretty dickish but wouldn't necessarily be Moral Event Horizon crossers in most stories have been cooked alive over a period of days and turned into human jerky, put in a cage with an angry ostrich (with Serge having a Black Comedy discussion with Coleman about how it is impossible to outrun those birds and they can disembowel a human with their feet as Coleman watches through binoculars and confirms that is happening just like Serge predicted), and simultaneously pecked to death by seagulls and given drugs that cause respiratory distress, seizures, and other painful reactions.
- When Serge is genuinely angry at someone and/or they're murderous career criminals, then his kills can be at their most nauseating. For instance, a homophobic pastor who has sex with underage girls in Naked Came the Florida Man is killed by being staked down and swarmed by an aggressive breed of mosquitoes that invade his orifices while biting to suck blood and eventually asphyxiate him. A man guilty of elder abuse in Clownfish Blues is put in a death trap where he has to eat hundreds of worms being herded into his mouth by sonic vibrations before they suffocate him (and Serge cheerfully tells him that he only has a 20% chance of survival). And in Gator-a-Go, one Mook has his hands set on fire and finds that every nearby water source he wants to put it out with has been shut down or filled with flammable liquid that makes the burning worse. Another goon is put inside an empty cement mixer and given a flashlight so that he can see when to jump over the blades. However, the flashlight has a low battery, and as soon as the light goes out, the man is quickly knocked off his feet by a blade he can't see and suffers "death by ten thousand blunt traumas. All minor enough to let him last for hours."
- Throughout Florida Roadkill, Beware the Silly Ones is much in play with Sharon, as she can be equally frightening as a merciless Femme Fatale (she kills one of her lovers by drugging him and getting his jeans wet until they shrink enough to cut off his blood flow) or an Addled Addict with a Hair-Trigger Temper (such as when she unexpectedly shoots two stingy customers at her strip club after they are helpless and her friends have already robbed them, and then seemingly forgets all about it when she sobers up). It's noted that Serge has become a lot more prone to casual violence since they began hanging out.
- In one prolonged scene in Orange Crush, a military unit in Kosovo finds itself trapped behind enemy lines, being stalked by veterans of ethnic cleansing campaigns. Then they find the body of the first local to happily welcome them, an old man who was waving a tiny American flag on a stick and has since been killed and had that flag stick shoved into his eye socket.
- Preston from Stingray Shuffle can be one of the most terrifying villains in the early books despite being a dorky Non-Action Guy uninvolved in any organized crime due to the sheer Paranoia Fuel behind his sexual assault methods (using hypnotism for Bed Trick rapes) and the legion of victims he has ensnared. They range from fellow college students to more college students when he got older and was their professor, to teenaged girls who obliviously volunteer for his stage hypnotism act with their families, to random people he bumps into on a train.
- In Stingray Shuffle, Ivan's team may be Stupid Crooks, but several of them are constantly eager to torture people below the belt with drills, a torch, scorpions, or electric shocks, even if Ivan keeps stopping them.
- In Torpedo Juice, guest character Anna goes on the run after the brutal, drug-related murders of her beloved brother, her sister-in-law (her former best friend), and her not-so-beloved husband, only to learn the killer is her new boyfriend and apparent only ally, who feels sexually aroused as he prepares to shoot her and she vainly tries to escape, right up until Serge intervenes.
- One scene in Hurricane Punch has Ax-Crazy Serial Killer "The Eye of the Storm" is seen in an enormous Room Full of Crazy writing a creepy letter to the writer of all the newspaper articles he's clipped out, Nervous Wreck Jeff McSwirley. This is eerie enough, but the climax reveals that the Eye of the Storm is McSwirley but that Jeff is oblivious to this due to a split personality.
- Most of the kills the McGraw redneck outlaw family commits in Triggerfish Twist and Atomic Lobster are pretty unnerving due to both their gruesomeness and them being more disproportionate than even the worst reasons Serge has ever had for killing someone. When they think their drug dealer sold them bad speed (when really it was quality narcotics that just made them irrational enough to think it was bad speed), they tie him to a tree and shoot his gut and legs multiple times before finishing him off. And even the rest of the family is horrified at the sight of Tex McGraw shoving his former lawyer's face into a barrel of boiling oil for a fish fry just because the man was unable to get him off on a murder charge where the police had mountains of evidence and caught Tex at the scene covered in blood.
- In Atomic Lobster, after Girl of the Week Rachael learns that her older sister was one of Serge's previous victims (and that Coleman stood by while it happened), she gets high on coke, attacks Coleman with a knife, corners him, and waves her knife around his face while talking about what vital parts of his face or groin she might cut up before killing him.
- Serge's intervention is no less disturbing. He shoves a fire extinguisher nozzle up to Rachael's face and empties it down her lungs. Then he calmly enthusiastically chats with Coleman about the mechanics of what he just did as they watch her thrash around the room, internally drowning and being unable to effectively pump her own stomach because, unlike water, the extinguisher foam residue clings to the walls of her lungs, blocking oxygen from entering the bloodstream.
- The sequence is even creepier given how Serge and Rachael have been in a (mutually unhealthy) relationship throughout the book and she has been accompanying Serge through his zany misadventures (albeit unenthusiastically and not very helpfully) but are still willing to try and viciously kill each other on such short notice (Serge and Sharon had premeditated plans to turn on each other for a briefcase of money before their final falling out). Serge even expresses regret that he didn't do so sooner and is even more celebratory than usual about getting rid of Rachael.
- In several books, Serge doesn't kill someone directly but puts them in a position where they're at the mercy of an angry mob driven into fury by Serge's targets stealing cancer treatment donations in Shark Skin Suite, jacking up the prices of life-saving pharmaceutical projects in The Pope of Palm Beach, and being a toilet paper price gouger during the COVID quarantine in The Maltese Iguana. On each occasion, the mob ends up accidentally causing the person or people to suffer a horrible death during their efforts to escape, and even readers who find those deaths cathartic might be a little unsettled about just how angry, widespread, and pitiless the mob mentality can get on those occasions.
- In Clownfish Blues, a bodega clerk who is a minor part of a money laundering scheme that involves lottery tickets is subjected to a You Have Failed Me fate of having rolls of tickets wrapped around his head until he asphyxiates.
