As expressed in the film "Mr Turner", Grabin' a book refers to sexual intercourse.

You often do this by walking up to someone in front of a book shelf and pretend to reach a book above their head. Do not let them move out of the way. Then you wrap your arms around them and so forth.
Also refers to either Grabin a pu*sy or F**king a pus*y
*Do not attempt this action in a Library*
"Hey, Did you see George back there at the book shelf with that lady? He was grabin a book!
by StEv097 March 18, 2015
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