These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Anti-Villain: Reverend Dr. Tan/The Narrator who generally just wants to make the world a better place. However, he resorts to murder and petty revenge as well...
The Bad Guy Wins: Depending on your interpretation of the ending, the narrator's Batman-Gambit may have ended like this. According to him, the cult succeeds and everything works in his favor. However, there are shades of Unreliable Narrator with this.
Moral Event Horizon: The Prefects cross it by beating Skimpole's son to death as their "payment."
Nice Job Fixing It, Villain: YMMV on how you define "fixing it." In an effort to see his plan go off without a hitch, the Reverend Dr. Tan hires Arthur Barge, aka the Mongoose, to kill the members of the Directorate. This prompts Skimpole to hire the Prefects, who kill Arthur, Trotman and most of Dr. Tan's army, buying Edward enough time to cause Coleridge to break down.
Ugly Cute: Moon's favorite type of prostitute. His current favorite is Mina, the bearded lady who has a thing described as a curious deformity, a grisly pink piece of flesh which bore a ghastly, visceral resemblance to the severed arm of an infant growing out of her chest.