The foil
Victor's story is suggested as a foil. This is shown in a few ways. For instance, they are the same age; they have similar temperaments and similar motivations; both are supposed to be in classes for their First Communion (a Catholic rite of entry), but instead, they set their minds to nefarious goals and trouble-making schemes. They play together and bring out the most daring, offensive sides of each other. As a foil, we learn that Andrea is on a dangerous path. Victor ends the plot by killing himself.
The disparaging
Andrea is an extremely spoiled child. She doesn't understand the difficult that faces these mid-century border towns. She feels that everyone should loosen up and have more fun, and she is chronically bored, because her privilege makes her life free from stress and responsibility. When other kids are working the fields, she makes fun of them and gets into trouble. She admits that she made her goal to do evil before noon each day. She disparages the less fortunate because she is sheltered from the harsh reality of life by insulation and privilege.
La mala mujer
These children are too young to understand the painful reality of life for the poorest of poor. Through the cracks of the floorboard, they find someone's secret; a local woman named Armida has been giving out sexual favors for money, "massaging" her clients to climax. The children know instictually that this isn't allowed, and although they literally dedicate themselves to sinning as much as possible, they decide to exploit this struggling woman for her vice. This woman symbolizes the hypocrisy of the children. They ruin a person's life with the same attitude they used to pull pranks, not knowing that this woman will be murdered for this.
The motif of giving and taking
When the children decide to rat on Armida, they also decide to steal her profits. They figure it is sinful money, made through sinful means, so they will steal it and help the poor. Of course this is a thin veil on their true intention, which is to take for themselves. While stealing from them, the kids realize the drastic difference between their lavish homes and these poor estates. They are taking from the poor to give to the rich, it seems. This symbolizes their true nature; they do not need money, but they steal from those that do.
Bloodguilt
Remember the premise of the novel; these kids are supposed to be preparing for their first communion. In the meantime, they decide not to attend Confirmation classes. Instead, they spy on a woman and exploit her for mild prostitution. In the aftermath, they hear about various suicides in the community and they are forced to witness a gang of angry men raping and murdering the woman they outed. Now what does that mean for their First Communion? Instead of approaching the altar with the innocence of children, they come with real blood guilt and a hefty experience of suffering, suffering that they actually caused. This brings Communion into its proper sacredness, because the children have adult guilt, they feel.
