He is not responsible
One of the most ironic ideas presented in the novel is the fact that Carlos is not responsible for his own actions or rather for the fact that he is unable to control himself when it comes to sleeping around with as many women as possible. Because of this, none of the characters criticize him or anything he does.
Women blaming one another
Because Carlos lived in a small community and slept around with almost every woman he meet, it was inevitable that at some point or another the women were going to find out about some past conquests Carlos had. Ironically, instead of blaming Carlos for playing with his feelings, the women ended up blaming one another.
The one who took care of him
Another ironic idea in the novel is the identity of the person who takes care of Carols during his last moments of life. This person is not someone who is related to Carols and is also a person who was never married to him. Instead, the woman who takes care of Carlos is a woman on whom Carlos cheated in his youth.
I will never do something like that
Throughout the novel, the narrator mentions a large number of women who refused to interact with any of the women Carlos slept with. These women saw themselves as being superior to those who got involved with Carlos. Ironically, however, almost all the women mentioned in the novel as being judgmental end up being seduced by Carlos and wanting to get involved with him.
The man who does not need anyone to take care of him
In his youth, Carlos mentioned time and time again that he does not need anyone to take care of him. Because of this, he refuses to get married and also refuses to mend the destroyed relationships he had with his relatives. Ironically, the man who claimed he needed no one ended up at the end of his life in the position to rely on others to survive.