He's not a delinquent, he's just un-photogenic.
From what I am seeing, pretty much. Also, if you look at one of the last panels over his head, you see number of drawings done by a child/children, likely his sibling(s).
My guess, he looks intimidating, but he is not attending school because of a gang, but because he needs to earn money to support his siblings.
Honestly, I like that tiny nod of images, as they are right at the front door where you will see them every time you leave and return, likely something he does both because he loves his siblings and also as a way to keep him driving forwards to keep working.