That night, Davis texts Aza and asks if they can hang out. Aza agrees. It's freezing outside as she walks from Harold to Davis’s front door. Davis leaves Noah on the couch playing video games and he and Aza walk outside. Aza tells Davis that she read Daisy's fanfiction and hates Ayala. Davis insists that he likes Ayala.
That Davis finds Ayala appealing only reaffirms for Aza that Ayala is a true-to-life representation of her own personality. In Aza’s mind, Daisy's fanfiction proves not just that Aza is a bad person, but also shows Aza that she didn't have any real understanding of Daisy's perspective of things.
Aza and Davis stop by the pool and sit on loungers. Davis worries about Noah and twirls his Iron Man. Aza tries to tell him that Iron Man isn't much of a superhero, but Davis changes the subject and tells her that the Milky Way galaxy is a massively huge spiral that rotates around a black hole. He asks Aza about her spirals. She tells him about Kurt Gödel, a mathematician who was deathly afraid of being poisoned. He only ate food prepared by his wife and starved to death when his wife was hospitalized and couldn't cook for him.
Aza's assertion that Iron Man isn't a great superhero is likely somewhat hurtful to Davis because he is so attached to his Iron Man action figure. Therefore, Aza is not just insulting Iron Man—she's actually insulting Davis. Davis introduces the idea that spirals don't have to be small and constricting. They can be the size of galaxies, though the black hole he mentions foreshadows what will happen when Aza reaches the center of her own spiral.
Davis asks Aza if she's worried the same sort of thing will happen to her. Aza says that it's weird knowing that you have a problem but being unable to figure out how to fix it because, like Gödel, you can never be sure the food isn't poisoned. Davis poses his question again, and Aza says she worries about many things.
Aza's story about Gödel mirrors her own relationship to medication. She can't bring herself to take it regularly, because she can't be sure that it isn't changing her in a negative way.
Davis asks Aza if she'd like to swim. He strips down to his underwear and jumps into the heated pool. Aza asks Davis to turn around while she undresses and then gets into the pool with him. Davis holds her in the water but doesn't try to kiss her. Aza notes that Tua is watching them, and Davis shudders and shares that he hates Tua. When they get out of the pool, they run without towels back to the house.
Not all the things that money can buy are charming for Davis: Tua is decidedly not charming. This reminds the reader again that Davis is a multidimensional character who, contrary to his worst fears, is not just the sum of his wealth.
Davis shows Aza his telescope. He focuses it on his favorite star, Tau Ceti, and explains that it's twelve light years away. He likes it because if someone were to see the light of Earth's sun from a planet in Tau Ceti's solar system, they'd see the light of the sun from twelve years ago, when Davis’s mother was still alive. Aza wants to tell Davis she loves him, but isn't sure if it's true. She understands why he loves the old stars and realizes that in three years, he'll find a star further away to remember his mother by. She thinks it's much the same reason why she looks at her dad's pictures. Aza leaves and Davis asks if they can hang out at her house next time. She agrees.
Aza and Davis are looking at much the same thing when they look at stars and photographs: they're looking at different arrangements of light that capture or represent a moment in time. Both of these formats for light work to give them a sense of control and order in their grief, and a way to mark the passing time since their parents' deaths.
When Aza gets home and tells Mom that Davis wants to come over, she answers Mom's questions about whether Davis is her boyfriend and properly listens to her. In bed, Aza checks Davis's blog. She reads one new entry, refreshes the page, and there's a brand new entry that addresses her directly—Davis knows she's reading. He posts a quote about "going out to the meadow," an expression from classical music that describes the feeling of playing music as though a musician isn't in a concert hall. Davis says that their conversation earlier was like that. The feeling they shared was important, not what they talked about.
Aza and Davis are formulating a sense of shared identity in their relationship, whether or not they put a label on it. Davis now uses his blog to address Aza directly, which shows that he's aware and feels in control of his audience on his blog, and is also an example of another way for him to use language to connect with Aza. Addressing her directly turns a static diary entry into something living and interactive.
Instead of going to sleep, Aza decides to read more of Daisy's fanfiction. She wonders how Davis can find Ayala charming, since Aza finds her self-centered and annoying. Aza then reads Wikipedia articles about fanfiction and Star Wars. She comes across an article that talks about the "gut-brain informational axis," which is the relationship between someone's gut bacteria and their thoughts. The thought that Aza's bacteria are indirectly controlling her thoughts is horrifying to her. She sneaks to the bathroom, changes her Band-Aid, and takes three swallows of hand sanitizer.
Reading the fanfiction fuels Aza's sense of self-loathing and continues to break down the closeness she felt with Daisy before she realized that Daisy might despise her. What she finds is even worse than Ayala: proof that bacteria are actually controlling her thoughts and feelings. This only confirms Aza's overblown sense that bacteria are harmful, and it leads her to swallow more hand sanitizer, which is definitively far more harmful than her imagined bacterial infection.
Aza's brain reminds her that clearing out healthy bacteria can make room for malicious bacteria like C. diff. Her stomach hurts and she tries to tell herself that drinking hand sanitizer won't make her clean or healthy. Back in bed, Aza remembers when Dr. Singh first asked her if she felt like a threat to herself. She wonders how, grammatically, that's even possible if she's both the threat and the self. As she descends into the spiral and begins to fall asleep, she asks whoever's authoring her to let her out.
Finally, Aza actually echoes James Joyce's Ulysses by asking the author to let her out of the story. At this point, Aza's identity is splitting further, and she tries to make sense of the split by considering how exactly it works grammatically. Here, she studies and questions the words themselves to understand how they inform her self-understanding.