Reading part but not all of a book is like surveying human anatomy & biology with all the reproductive organs/references removed.
Either don't allow the book or allow the entire book.
Especially if it is for a comparative analysis.
In this case I'm pretty confident the sexually explicit pages were endemic to the overall story line.

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I did not win the Powerball again!


"When a true genius appears in the world, you may know him by this sign, that the dunces are all in confederacy against him."
--Jonathan Swift