Naomi and Tina are identical twins. So nearly do they resemble each other that when Naomi first arrives in Knockemout, she is confronted again and again by townspeople who mistake her for her rogue sister. Conventional understanding suggests that twins share a sensibility in which they are essentially parts of a single personality. Here, twins function differently as Naomi and Tina are each other’s foils.

The novel uses the idea of twins to explore alternate personalities. As Tina and Naomi grew up, their personalities moved in opposite directions. Tina took risks, defied authority, and deliberately upended her home and school life. When she had the opportunity, she broke free of any parental guidance. Rather than mirroring her sister’s unending rebellion, Naomi countered her sister’s behavior. As a result, she was never sure whether attending school, following rules, and respecting adults was who she was or just who her twin was not.

Because of this, Naomi arrives in Knockemout uncertain of her identity. Tina is less Naomi’s twin and more her foil: the classic “evil twin” archetype. Naomi goes so far as to call Tina her “evil” twin as she confronts the reality of how much of her she has wasted cleaning up her sister’s messes.