In Chapter 4, which covers the period 1988–1992, the narrator at last reveals his identity. His name is Yunior, and he explains how he became involved with the de León family. He met Lola in college at Rutgers. One night during their sophomore year, Yunior got mugged, and Lola was the only friend to show up and help tend his wounds. Not long after that incident, Yunior and Lola had a brief affair, but Lola ended it because she felt guilty about cheating on her boyfriend.
Oscar also attended Rutgers, and at the end of his freshman year, he nearly drank himself to death when a girl rejected him. Afterward, nobody wanted to room with him. In a bid to impress Lola and to ensure that he’d have university housing, Yunior offered to become Oscar’s roommate.
Oscar’s nerdiness surprised Yunior. He notes, for example, that Oscar had put a sign on the door that said, in the Elvish language of Sindarin, “Speak friend, and enter.” Whereas Oscar spent most of his time in the apartment, Yunior initially kept himself scarce. But gradually they became friends. Like Oscar, Yunior wrote fiction, and they occasionally exchanged work. Yunior also tried to help Oscar find the confidence to approach women.
Near the beginning of the new school year, Yunior’s love life imploded after he cheated on his girlfriend. He took his mind off his relationship troubles by helping Oscar try to change his life. He encouraged Oscar to adopt new dietary habits, avoid self-criticism, and exercise. Oscar quickly grew fed up with Yunior’s harsh program and quit, which caused a rift between them. Yunior and his buddies started bullying Oscar. One day, Yunior said that Oscar looked like “that fat homo Oscar Wilde.” His friend Melvin misheard him and asked, “Who is ‘Oscar Wao?’” The nickname immediately stuck.
A fellow student named Jenni Muñoz helped bring an end to their feud. Jenni was a hardcore goth who lived on the second floor of their dormitory. Yunior tried flirting with her once, but she blew him off. During the period after their falling out, Yunior noticed that Oscar had eyes for Jenni. One day, Oscar approached her, and, to Yunior’s surprise, she agreed to go out with him. They started spending time together. Oscar resumed his exercise routines and took more care with his appearance. Oscar’s transformation sparked jealousy in Yunior, who asked, “How can you be in love? You just met the bitch.” Oscar replied darkly, “Don’t call her a bitch.”
One day, Oscar’s mood took a sudden turn for the worse. Yunior suspected that Jenni had rejected him, but Oscar refused to talk about it. Two weeks later, at the end of the school year, Oscar walked in on Jenni having sex with another guy. Furious, Oscar attacked Jenni and called her a whore.