The death of Narciso causes Antonio to question why good people are punished while evil people like Tenorio remain unpunished. It turns out that the cops chalked up Narciso's death to a drunken accident or a self-inflicted gun wound. They didn't take the fever-ridden Antonio's word as truth.
Tenorio confronts Antonio one day after school. This is a huge moment, because Antonio does his best to stand up to Tenorio, yelling, "You are a murderer!" (16.91). Touché.
Again, Tenorio claims he will find a way to kill Ultima. Antonio warns Ultima of Tenorio's plotting, but she tells Antonio not to be afraid for her. Um, easier said than done, lady.