Minerva McGonagall and Dolores Umbridge during the Order of the Phoenix books. My first piece of these two (three? four years ago?) proved to be quite popular. It was, however, long due for an update.
They are in a classroom: the bookshelf was put in to fill empty space without being too busy. I have no explanation for the lighting - it just happened. McGonagall had a tartan shawl until I realized that it was threatening to take over the entire piece and banished it. Tartan will do that if you're not careful.
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