During their first night together, Secundus reveals his quest to Boy; he is seeking seven relics from the body of Saint Peter: "Rib tooth thumb shin dust skull tomb".

The story is set in the holy year of 1350, while the Black Death was sweeping through Europe; before the novel begins, the wife and three children of Sir Jacques have succumbed to the plague.

Murdock noted she was influenced by Susanna Clarke's Jonathan Strange & Mr Norrell, developing the dialogue to balance accuracy in historical vocabulary with readability for modern audiences.

"[2] Christopher Healy, reviewing for The New York Times, had mixed feelings about "the artistically ambiguous ending" which "gives no explicit answer to the question [of whether Boy should hide his true self]".

"[4] In her review for School Library Journal, Elizabeth Bird also called Boy "the living embodiment of kindness and joy" and drew a contrast to the current state of children's literature: "We have a lot of dark, depressing, necessary books out there.