Hopkins's titles are always one word, and this one's easy: Perfect is a book about being perfect. The big question here is who defines perfection. As Cara says on the first page, "Only you should decide for you what is perfect" (1.5-6). And on the last page, she describes the letter her parents wrote to Conner as being "folded into […] a perfect paper airplane" (57.16-17). Being pushed toward perfection is something you either find freedom from or collapse under the weight of, and each main character in this book navigates this struggle in their own way.