Thank you for your long, thoughtful comment. I'm so glad that you enjoyed it. I always thought that Snape was a smoker (stained teeth and fingers, pasty complexion, thin build - all suggests a heavy habit to me) and like my own teachers at school, he'd sneak out for a quick smoke in the lunch break and feel guilty about it.
I love Watson as a narrator, he is a good man; sympathetic, broad-minded and intelligent and yet of his time, that type of middle-class, Christian, white, British man who assumed that all woman were either ladies or fallen women, that other 'races' were slightly inferior and that to be English was to have great power and great responsibility. I love contrasting his attitudes with those of the twenrieth century wizards.