My advice for this week is to really understand both your story and your characters before you begin. Who does your character accidently read out? What happens? Does the character run away, does the character want to go back? Have a clear idea of what's going to happen.
Next is to understand both of the characters. The best way to do this is to "interview" the characters. When I was reading about this method instantly one of my characters that I've been thinking about for a long time spoke up to answer the questions. I thought to myself, Heidi when did you get so feisty? And just learned that Heidi is tired of sitting on the side and maybe I should keep writing her story. Laurie Campbell has a great page with interview styles and questions to ask your characters. The different methods include:
1. 20 Questions: asking your character open ended questions that have to have a full and specific answer.
2. Basic Inventory: questions as simple as their name and how old they are.
3. Gloves off Questions: Questions that really make your character think about the answer.
4. Free Style Interview: Basically having a conversation with your character about how they feel the story is going.
I personally like the Gloves off interview. Heidi spoke up when I read the question "what do you want?". Now, I also find the interview method a little disturbing. You are, technically, asking the voices in your head how they feel about this or that, and they have to answer. But remember that characters are people that you have created, and they only way they can escape your head is for you to tell their story. For this prompt I recommend doing this for both characters. Especially for the character that's being read out of the book, since they aren't yours to begin with.
If you're really interested in character development then I recommend The Writing Practice . Which by the way, you could totally leave me for this guy and grow just as much as a writer. But don't do it, because I would be really bummed.