At first, Hopper thinks that the strange birds that live around Stately Academy are creepy. Then, she and Eni realize that they are visual illustrations of how binary code works. When certain numbers are shown to them, they change the configuration of their four eyes to display that number in binary code. This happens when they see Hopper’s number seven earrings, the large number nine painted on the school’s exterior walls, when Mr. Bee shines a 15 at them, and when Hopper shows them the zero on Eni’s basketball jersey. They respond to each number differently because Mr. Bee has programmed them. Because binary code and computer programming are abstract concepts, the birds are useful as a visual and concrete display of binary code for Hopper and Eni, as well as for readers who are learning about coding. Throughout the novel, the birds are simultaneously symbols of binary code, active participants in the plot of the story, and elements that add to the creepy environment of Stately Academy. Because they are controlled by Mr. Bee and he has them attack Hopper and Eni, they have a sinister feel to them.