The chapters in this group might be said to have a common theme — mystery, or perhaps ambiguity. The first four are concerned with people, incidents, and feelings that are mysterious to Esperanza in various ways. The fifth epitomizes the emotional ambiguity of adolescence, the feelings of anger and longing that Esperanza usually keeps within herself.
Geraldo "No Last Name" is himself a mystery that will never be solved, because he is dead and no one knows anything about him except that he was from Mexico. His family will wonder what became of him — probably they were depending upon money he was sending home — but there will be no way for them to find out. Marin, although she had danced with him, knew nothing about him and couldn't remember where he said he worked. And why was Marin with him at that hour? Had he seemed likely to take her to a fine house far away? Whatever the case, he had touched her deeply enough that she waited at the hospital, where he was not saved — although he might have been, had he been luckier in several regards (including, Esperanza implies, luckier in his color, language, profession, and economic status — but then he might not have been walking at 3 a.m. with Marin).
In fact, there is probably only one place where a young man who rents a sleeping room in the city might have been going with Marin at 3 a.m. Whether they were going to his room or leaving it, walking to where Marin might catch a train or bus home, we will never know, as Marin is not heard from again in the book. But we know that Marin, surely no older than 15 and probably not quite that, would not go to a young man's room without being "in love" with him, even if that love was of only a few hours duration, even if she had never learned his last name. Of course she would not be cold enough to leave him dying alone, although her presence in the waiting room could not help him.
