Coming of Age
At its most basic level, this graphic novel is a coming-of-age of story about that moment in life where the transition is made from innocence to experience. This type of novel is often categorized within a genre known as Bildungsroman which is really just a fancy literary term intended to cover the all the bases within any story that is about growing up and maturing. Rose and Windy are co-protagonists of the novel within this theme as both are much younger metaphorically as the story begins than they are at the end.
Sexuality
While both girls age metaphorically by novel's end, there is also a theme which addresses their literal age. Rose is a year-and-a-half older than Windy at a time in life with eighteen months can feel like several years. As a result of the age difference, of course, Rose is dealing with the mysteries of sexuality more viscerally than her slightly younger friend. Adding to the overall patina of sexuality as a thematic engine driving the narrative is the fact that the overwhelming depression affecting Rose's mother is impacted to a great degree by issues related to a failure to produce more children. Also of significance is local teenage girl struggling with an unwanted pregnancy.
Depression
The depression of Rose's mother is not simply a case of the blues, but rather a clinical form of the condition either brought on by or worsened by a relatively recent miscarriage. Alice's own issues with an inability for sexual intercourse to produce another child cannot help but become bound up with her obvious awareness of Rose's own suddenly burgeoning sexuality. The theme becomes narratively significant later in the novel when her story becomes inextricably intertwined with that of her symbolic opposite, Jenny.
