The irony of sexual shame
Sexual shame is at the center of the novel's drama. Ironically, the society around the story views women differently than men, because women are made to feel incisive, specific shame—there are still many, many men and women who judge their partners harshly for past sexual experiences, but in general, the effect of this novel is that for Yunior, there was some sort of immunization against shame. He never feels the full weight of his shameful sexual behavior, primarily because he is a man, and that changes the kind of feedback he gets from his peers.
The irony of helpful gossip
This novel paints gossip, a historically vicious idea, in a positive light. Actually, in a social economy whose currency is innocence, there is something at stake, either real or perceived, if a girl thinks she is going to marry a person, so she has sex with him, and then he abandons her. Such behavior is literally the worst case scenario, and Yunior inflicts that doom on his girlfriends casually. It is helpful that they share the truth about his behavior, even though gossip is frowned upon in general.
The irony of innocence and guilt
Yunior is guilty of social indiscretions, and he makes his mistakes in private, not out in the open, but this novel brings his drama out quickly when the girl he cheated with tells everything in a letter to the girl he cheated on. That is where his experience of innocence starts to become twisted. The irony is that Yunior doesn't stop to consider that there might be other reasons to behave differently, other than guilt. His defensiveness is ultimately self-destructive.
The irony of life's test
Death makes a major appearance in Yunior's story, because his own brother's life comes to a tragic end when he is diagnosed with terminal cancer. Ironically, that causes Rafa to do the best thing he can for himself, to provide himself the maximum support he can to face his death, he commits to a specific girl whom he admires. Then he passes the test, because in the end, although Rafa is dead, he is at peace, but Yunior has isolated himself, and no one wants to date him anymore.
The irony of family, love, and sacrifice
Apparently, the truth about love is ironic in Yunior's case, but his family is literally enduring so much that ironically, the only way he is even surviving in America is because of the hard work of his family. He lives a life that is built on the sacrifices of his family before him, but ironically, he doesn't really love people yet. So, he doesn't sacrifice anything for anyone except himself, and therefore, his participation in his own family is too limited to be helpful to him.