What role does the idea of what defines true masculinity play in the novel The Brief Wondrous Life of Oscar Wao?

The male characters in the novel struggle to achieve a positive, healthy masculine identity in part because they lack role models. The two protagonists, Yunior and Oscar, present two contrasting views of masculinity, although these differences are somewhat lessened by the end. Yunior embodies a more conventional, even stereotypical version of Latin American masculinity or machismo. His physical fitness and attractiveness to women are important to him, but he devalues women with his constant infidelity.
One of the more positive aspects of his masculinity is the protective role that he plays with his friend and roommate, but he is also arrogant in believing that Oscar’s problems can be easily fixed. Oscar is distinguished by his sensitivity and creativity, and his extreme weight keeps him from the social world of athletics in which other boys are absorbed. Nevertheless, Oscar’s strong heterosexual desire, couched in romantic idealism, makes him as much an embodiment of traditional masculinity as Yunior is. The minor characters, such as the Gangster, represent the negative force of excessive machismo, including violence and abandonment.