There is no need for printed books
During the first conversation Joe has with Guinevere, he mentions how because of the way modern world is, there is no real need for printed books and for people to have printed books in their homes. From the way Joe talks about books, it may be understood he detests them and everyone who may value them. Because of this initial attitude, it is ironic to see how Joe criticizes those who do not behave in a proper way with their books and who do not chose what are in his opinion, worthy books of reading.
Not so pure
Soon after the initial meeting between Joe and Beck, Joe develops an unhealthy obsession with the young woman and starts following her. He soon realizes Beck was not the pure woman he believed her to be but rather was extremely dirty and sexual active. This realization is ironic especially when considering the initial view Joe had on Beck.
Should have run the first time
Shortly after the first contact between Beck and Joe, the two find intimate details about one another. For instance, Joe learns about the affair Beck had with her therapist while Beck finds a box filled with copies of her emails and pictures of her which Joe acquired while stalking her. Ironically, instead of breaking all contact with Joe, Beck continued to seek his company and to call him when she felt most vulnerable.
Finding the perfect woman
When Joe realized there was little chance of Beck agreeing to be with him in a real relationship, he began his search for a suitable partner. Joe eventually found a woman whom he agreed was the perfect girl for him, the one with who he could find happiness. What is ironic to see is how, despite Joe knowing he will not be happier with Beck, he still decides to break up with the woman he saw as being the perfect one.
Not the only one
The novel ends when Joe kills Beck when she tried to escape from the cage in which he kept her in. In the beginning of the novel, Joe was so in love with Beck he was sure he will never feel something similar for another woman. His initial thoughts are ironic because after killing Beck, he saw another woman enter the same bookshop where he met Beck and he felt the same things he felt for Beck in the beginning.
