* AlternativeCharacterInterpretation: When Ig asks Merrin's father what Merrin might have said to him before her murder (while trying to find info on if Merrin was seeing someone else), her father refuses to say anything to the man who allegedly killed his daughter. Is that the only reason? Or could it be that Merrin asked her father not to inform him of her cancer diagnosis, and he is merely honoring his dead daughter's wishes.
* CrossesTheLineTwice: During the climax, [[spoiler: Lee blows Meatbag's head off with a shotgun while struggling with Ig - Lee promptly does a SpitTake at the surreality of the situation]].
* GeniusBonus: The end papers of the hardcover edition show a Morse code message that translates as "Pleased to meet you, hope you guess my name" -- a line from "Sympathy for the Devil" by Music/{{The Rolling Stones|Band}}.
* HilariousInHindsight: Multiple points in regards to the ''Literature/HarryPotter'' books:
** Ig at one point mentions that he hasn't read them. In the movie, he's portrayed by Creator/DanielRadcliffe, who played Harry.
** Ig's full first name is Ignatius. Harry is a descendant of Ign''o''tus Peverell.
** One of the powers of the horns is the ability to control snakes. Both Harry and Voldemort speak Parseltongue, the snake language.
* TearJerker: Merrin's letter to Ig explaining the real reasons why she tried to push Ig away.