Research has shown that putting a dog in a costume will invariably end with the dog promoting books and reading. Try this experiment for yourself by dressing up a dog in a costume. By the end of the day, it will have convinced at least three children to visit a library.
I'm trying to figure out what the boy was cosplaying as, and I can't determine if he's Wolverine or a Diclonii from Elfen Lied with visible vectors, but those are some straight-edge running hands.