Green parallels Quentin's obsession with Margo by having Quentin's teacher Dr. Holden lecture on Moby Dick. Green writes, in the voice of Dr. Holden, "You never see Ahab wanting anything else in the whole novel, do you? He has a singular obsession. You can argue...that Ahab is a fool for being obsessed. But you could also argue that there is something tragically heroic about fighting this battle he is doomed to lose"(p.159). After this, Green, back in the narrating voice of Quentin, writes, "I wrote down as much as I could of what she said, realizing that I could probably pull off my final reaction paper without actually reading the book"(p.159). Irony is created because though Dr. Holden is posing insightful questions very important to understanding Quentin's struggle - such as whether he is a hero or a fool, something Margo will bring up himself - Quentin clearly will not listen, even demonstrating uncharacteristic disregard for school, which is one of the effects of his obsession with tracking Margo.
The reader may find it frustrating that Quentin, Ben, and Radar find and decipher Margo's first clues in a matter of a few pages and then stretch out the finding and deciphering of her later clues over the course of hundreds of pages. The irony of this turns out to be that what were presumed clues throughout the book were never meant to be clues in the first place. The most obvious of this dramatic irony upon re-reading is Quentin's poring over "Song of Myself" for bits of knowledge on Margo's psyche when in actuality she meant for him to read two highlighted lines literally and never herself understood the poem very well.
Quentin's relationship with his parents includes some moments of comical irony because of their focus on his psychological well being, making them different than the average parents in surprising ways. An example of this is on page 106 when Quentin calls Margo's parents assholes. Quentin narrates "My parents always liked it when I cursed in front of them. I could see the pleasure of it in their faces. It signified that I trusted them, that I was myself in front of them"(p.106). This irony calls attention to the differences between Quentin and Margo's upbringings, which has had an effect on their ability to cope with stress in differing ways.
Quentin's Feelings for Margo
On page 176, Quentin is asleep in the mini mall and dreams of Margo lying next to him with her head on his shoulder. When he awakes to a call from Ben, he briefly notes, "God help me. The only teenaged guy in America who dreams of sleeping with girls, and just sleeping with them." Quentin's view of his attraction to and relationship with Margo is ironic because he views himself apart from other boys his age but truly behaves toward Margo in much the same way - sexually objectifying her, seeing her as an object to be chased and won, and not truly understanding her individual personhood and ability to make choices.
Paper Towns Questions and Answers
The Question and Answer section for Paper Towns is a great
resource to ask questions, find answers, and discuss the novel.