Prosper is the protagonist of the novel and the gang’s moral compass; a large percentage of the book unfolds in his point of view. At the beginning of the novel, he’s a 12-year-old boy who must suddenly take over caring for his brother, Bo, after his mother’s death. Prosper does not resent the responsibility; he loves his brother and doesn’t want to be separated from him by his aunt and uncle, so he runs away with Bo to Venice. He joins the Thief Lord’s crew to support his brother and finds a home in the Stella with the other children, but he doubts whether he did the right thing bringing Bo to the city. The boys’ aunt and uncle are wealthy and might’ve taken better care of Bo, and he is worried about Bo learning to steal. His doubts reflect the selflessness of his love for his brother—he wants the best for Bo, even at a cost to himself—as well as his strong sense of morality. Prosper himself tries to avoid becoming involved in the gang’s thieving and has conflicted feelings about ending up being the best loot seller.