I finally found it on Amazon; it popped up on Related to Items You've Viewed.
It is a book by Danish Author Mikkel Birkegaard and it is called Libri di Luca, or in English The Library of Shadows, published in 2007 in Danish and 2009 in English.
From the description on Amazon:
Imagine that some people have the power to affect your thoughts and
feelings when you read, or they read a book to you. They can seduce
you with amazing stories, conjure up vividly imagined worlds, but also
manipulate you into thinking exactly what they want you to.
When Luca Campelli dies a sudden and violent death, his son Jon
inherits his second-hand bookshop, Libri di Luca, in Copenhagen. Jon
has not seen his father for twenty years since the mysterious death of
When Luca's death is followed by an arson attempt on the shop, Jon is
forced to explore his family's past. Unbeknown to Jon, the bookshop
has for years been hiding a remarkable secret. It is the meeting place
of a society of booklovers and readers, who have maintained a
tradition of immense power passed down from the days of the great
library of ancient Alexandria. Now someone is trying to destroy them,
and Jon finds himself in a fight for his life and those of his new