It's particularly difficult to draw comics about modern literature, for two reasons: first, not nearly as many people have read the source material, unless it's something like Harry Potter - this makes the jokes less "gettable"; second, I probably haven't read the source material, so it requires more research. Still, if you throw down ten bucks, I do my homework. In this case, we have "The Wizard's Dilemma", the fifth book in the Young Wizards series.
The series began in 1983, predating Harry Potter by well over a decade. Checking the author's website, she seems sort of passive-aggressive about this fact. Seriously, read the first question on her FAQ. You just know she's probably gotten that question about seventy-thousand times and wants to put her fist through someone's skull.
I was specifically requested to draw a comic about one of the more depressing scenes in the series' recent history. Apparently, things have gotten quite a bit emo in the world of the Young Wizards lately. Scanning the internet, few things sounded quite so depressing as the heroine's mom getting a brain tumor, so here we are. Granted, cracking wise about someone's mom being on death's door isn't something I'm particularly proud of, but I was asked to mock something depressing, so mock I did.
As an aside, it's worth noting how incredibly helpful Google Books is sometimes. Entire chapters of this book are actually online and OCRed, so I could easily search the book for what I needed and quickly read up on the story. Thanks, Google!
And yes, our hero really gives the school bullies lung cancer, or at least hospitalizes them with smoke inhalation. Wizards are jerks.