Reactionbook
A form of audio or video content. A person reads a books creating an audiobook and adds commentary of their ideas/thoughts on top of them. Therefore it's called a reactionbook or reactbook for short.
Dude 1: "Man you love reaction videos on youtube, why not try reactionbooks?"
Dude 2: "Man I hate reading and audiobooks"
Dude 3: "Nah man reactionbooks are easier than reading and more entertaining than audiobooks"
Dude 2: "Man I hate reading and audiobooks"
Dude 3: "Nah man reactionbooks are easier than reading and more entertaining than audiobooks"