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Category: Book Title
Letters Left A B C D E F G H _ J K L M N O P Q R S T U _ W _ Y Z
_
Here is a pair of hints. The letter is one of the initials of a character in the book. However, in a different context, unrelated to the book, it also stands for a software language.
This book has received some terrible reviews, so don't expect to find it on anyone's top 500 list.