Lang, I haven’t read the book. Neither have you.
So I’m not going to attempt a discussion of the plot line or characters.
Because none of us has read the book. So we don’t know what the characters do, think, feel, say, or learn or decide or anything else.
Because we haven’t read the book.
Happy to have the discussion if anyone want to actually read it, all the way through, and then talk about it.
It’s a standard literary criticism question format by the way:
What role does character x play in relation character y in the novel?
It’s very commonly used in primary and secondary level English classes and tests.
I expect that’s why it’s phrased that way, and no, I don’t think it’s a leading question. Often the same question is posed with x and y switched as well, to really get students to dig into the the subtleties of what “in relation to” means in this type of question.
A leading question, for example (And yes, I know no one has said this, it’s for illustrative purposes only), is “do you agree that usborne books are utter idiots for posting this anti-women tweet on their feed?”