Who are Geno and Mouseface in the memoir, Undocumented, and what is their importance?

Geno and Mouseface are two members of a street gang that bullied the author for several of his school years. The bullying started with Geno, who believed that the author was spending time with his girlfriend, and was supported by Mouseface, whose real name is not given and who was portrayed as more of a follower of Geno than a leader in his own right. Later, the author says, after Geno was put in juvenile detention, he and Mouseface made their peace, another indication that the real tension with the author originated with Geno.