Yunior is the protagonist of eight of the nine stories in the collection. He is an immigrant who arrived from the Dominican Republic somewhere between ages six and eight and became a world-class scholar and writer. Díaz himself has acknowledged that there are many autobiographical aspects to his characterization of Yunior.

Yunior is brother to Rafa and son to Mami, who comes accompanies her children from the Dominican Republic to the U.S. to reunite with Papi, Yunior and Rafa’s father, Papi. Papi personifies the hypermasculinity Yunior says is common to Dominican men, as does Rafa. It is in part from these role models that Yunior learns how to be a sexual being. He cheats on girlfriends and lovers consistently and flagrantly, as have his older, male family members. Moreover, it’s rare for Yunior to harbor any genuine remorse about doing so, until the collection’s final story.

Rafa is Yunior’s older brother, a tough guy and athlete who obstinately battles cancer and dies. Yunior says, “He prided himself on being the neighborhood lunatic, wasn’t going to let a little thing like cancer get in the way of his official duties” (93). He is intense and bright but burns out quickly.