One of the first key signs that Nightbitch is turning into a dog is the unexpected growth of hair on her body. She finds, at the novel’s start, a “patch of coarse black hair sprouting from the base of her neck” (3), the growth of her eyebrows, “two black hairs curling from her chin” (4), and the shadow of a mustache. On top of this, the hair on her head becomes unruly, resembling “a cloud of wasps” (3). At first, these developments concern her. Nightbitch initially experiences these changes as something unpleasant happening to her, like an illness. However, as the novel progresses, and Nightbitch starts to embrace the animal side of her nature, so too does she embrace the hair growth on her body. After killing the animals in the woods she “stop[s] shaving her armpits, her legs, the tender folds of skin at the top of her legs and the mound of hair that grew at her center” (183). She experiences an “all-over furring of her body” and expresses the wish to “never brush my hair ever again” (180, 178).

In Nightbitch, hair growth represents the liberation of instinct and nature from the repression that human society imposes upon it.