The Possession of Mr Cave By Matt Haig

Terence Cave, owner of Cave Antiques, has already experienced the tragedies of his mother's suicide and his wife's murder when his teenage son, Reuben, is killed in a grotesque accident. His remaining child, Bryony, has always been the family's golden girl and Terence comes to realise that his one duty in life is to protect her from the world's malign forces, whatever that may take.