Who is the antagonist in part 2 Born a Crime?

There are differen antagonists and antagonistic forces through these chapters. Here is one:

Chapter 9: a group of older boys throws mulberries at him. His mother thinks the incident is funny, but when Noah tells Abel what happened, he realizes he can manipulate Abel's anger in order to get revenge. Sure enough, Abel tells Noah to take him to the boys who bullied him. Once they find them, Abel catches one of the children and whips him with a tree branch. Watching the violence, Noah experiences first pleasure and then horror. The boy's father later comes to the house to confront Abel but ends up also being frightened of him.