I think one of the aspects of this story that most strikes me is the way in which the character of Rose's father develops at the end of the story and we realise that there was significantly more to his character than both we and Rose first assumed. He is never named, and mainly appears to be the person responsible for the "royal beating," but we do know that when he recites poetry and sings, he is a figure of the imagination for Rose. It is only after she discovers his notebooks after his death that she begins to appreciate that there were whole new depths of her father that she never knew the existence of. She is forced at the end of this story to reassess her view of him and also to realise that humanity and identity is not something that can easily be captured or pigeonholed into one description.
This theme of the broadness of what it is to be human is something that is captured in many different works of literature through the ages. Perhaps we can relate this story though to The Colour Purple and the relationship of the protagonist to her husband, who used to beat her, and how they end up together once again. You also might like to think about other stories that feature domestic violence and the way that it is portrayed.