Zero's real name is Hector Zeroni, but he has been called Zero for most of his life. He has been homeless for most of his life, and his mother abandoned (or lost) him when he was still small. Zero has not had much of an education so he does not know how to read or write. Despite all the adversity that he has faced, Zero knows that he is smart and he has a sense of standing up for himself. At first he is presented as a strange character because he rarely speaks and always walks around with a scowl on his face. Eventually, when Zero becomes friends with Stanley, the reader learns that Zero is silent because he does not like answering questions and most likely because he is wary of people like Mr. Pendanski, who always mock him. Zero has suffered so much hardship in his life that he eventually cannot stand Camp Green Lake anymore and he runs away. He has a generous spirit, exemplified by the fact that he shares his last jar of "sploosh" with Stanley after he has run away. As Stanley gains self-confidence, Zero begins to talk more and scowl less. Zero is also very honest and although he steals because he lives on the street, he tries to steal less valuable things so that people will not mind as much. It is really Zero who has stolen the shoes that Stanley was accused of stealing and Zero feels bad for Stanley and apologizes for stealing them.