Dangerous criminal
Inquisitor is confident that Jace is a very dangerous person for the society. “Of course she thinks that he is a dangerous criminal”. But Jace makes fun of her, because he realizes that “he is just a very naughty boy”. He jokes that he is only able “to do all sorts of bad things such as to kick kittens and make rude gestures at nuns.” The irony is that Inquisitor is not sure in Jace’s safety, but actually he is a Shadowhunter, who struggles with evil.
Bad humor
After the rainy weather Isabelle comes back home and her hair and velvet coat are wet. But despite this bad weather, she has a nice mood and says “that is fun”. But Jace “is going to get her a dictionary for Christmas this year, because he is confident that she doesn’t know what “fun” means”. The irony is that Jace doesn’t know anything about the merriment and he always uses his black humor.
Deceptive soul
Isabelle affirms that she is “pure at heart. It repels the dirt”. But Jace snorted so loudly and says that her heart is “filthy inside and out”. Jace jeers at her sister, because he thinks that she is a bad philosopher and thinks highly of her not quite sinless soul.