Rennie is depicted as someone who feels overwhelmed and perhaps intimidated in a conversation, highlighting her reluctance to respond directly. The description of her as looking like "a whole book and a couple of extra chapters" implies that her expressions and demeanor are filled with unspoken thoughts and emotions, suggesting depth and complexity in her character.

This moment illustrates Rennie's internal struggle, hinting that she has much to say but holds back due to fear or uncertainty. It emphasizes her character's development and the challenges she faces in voicing her thoughts in the narrative of "Thirteenth Child" by Patricia C. Wrede.