Who is Julio from My Bloody Life: The Making of a Latin King and what is their importance?

Julio was Reymundo's friend at Von Humboldt School, during his first year in Humboldt Park. The boys played baseball and football with the Western Boys sports team. Other team members included Jorge and Noel. Years later, a Spanish Cobra confronted Reymundo with a shotgun. It was Julio. They recognized each other, and Julio let his friend escape.