Inexperienced Simon
It is a full astonishment for Jace to hear Eric’s poetry. He affirms that “his poetry is terrible”. And “it sounds like he eats a dictionary and starts vomiting up words at random”. This is an ironical moment since Eric is sure to be an excellent poet, but actually he writes awful poetry. Sometimes, one’s expectations cannot be fully fulfilled
Difficult magic
Jace always tries to explain Clary the meaning of a magic that it is “not just a lot of sparkly wands and crystal balls and talking goldfish”. He also plays tricks on Clary and says that just because she calls an electric eel a rubber duck doesn’t make it a rubber duck”. The irony is that Clary doesn’t have an idea of the magic, even when Jace repeats this over and over. It is incomprehensible for her, is fact she does not just feel it, she tends to see the things that are, and to see magic as something definite.
Self-confidence
Here the author wants to ridicule Jace’s confidence. He is assured that Clary likes him very much. And when Clary says that “he can start tearing strips on his T-shirt to bind up her wound”, certainly Jace says that “she wants him to rip his clothes off”. She just needs to ask him about it. The self-praise of men is an irony here.
Spoilt girls
Clary laughs at men, because they don’t understand whims of women. She says that “when most girls say they want a big rock, they don’t mean literally a big rock” and with this quote she proves that all women are grouchy. The irony is based on that fact that it is difficult to take hints of girls and sometimes they don’t know what they want themselves.