According to Yunior, the narrator of much of The Brief Wondrous Life of Oscar Wao, the whole story itself is an account of fuku, the curse that has plagued the De Leon and Cabral families for so many years. In telling the story, Yunior believes that he is invoking the power of zafa, a supernatural force that is somehow meant to ward off the destructive counterforce of fuku.
The concept of fuku, or to give it its full name, fuku americanus, is intimately linked not just to misfortune in general but specifically to misfortune that leads to violence. It is apparently a traditional element in Dominican folklore, one that conveys a sense of fatalism among those who fall under its unbreakable spell. Throughout the story, this supernatural understanding of cosmic fate manifests itself not just in relation to the heritage of violence bequeathed by the Trujillo regime but in specific acts of violence carried out by individuals.
We see this point illustrated most strongly by the effect that fuku has upon Oscar. His vivid imagination, combined with his cultural background, encourages him to believe that he is cursed to die a virgin as he persistently fails to attract girls. After one particularly humiliating rebuff from a girl at college, he attempts suicide, an act of violence against the self. A subsequent attempt by Oscar to take his own life by jumping from a bridge merely serves to emphasize the tight, unrelenting grip that fuku appears to have upon him. Then, finally and tragically, there is the brutal beating and eventual death that Oscar receives at the hands of Solomon Grundy and Gorilla Grod.
But in both these examples, it might be helpful to look at fuku not so much as a supernatural concept but more as a thoroughly natural one. For in a sense, Oscar finds himself trapped by his cultural heritage, one that imposes upon him certain expectations of how a Dominican male should behave. His failed attempts at finding love, for example, are really more concerned with proving his machismo than expressing a genuine desire to settle down with the right girl.
Moreover, the imposition of cultural norms lurking behind the whole notion of fuku encourages Oscar not to take responsibility for his own destructive actions. The same principle applies to other characters in the book; no matter how selfish, violent, or harmful their behavior, they can always blame the unfathomable, mystical forces unleashed by the great fuku curse.
It could be possible then to see the character of Oscar as a symbol of the Dominican culture by whose norms he lives and ultimately dies: a culture in the viselike grip of a curse all of its own making.