Who is Jay from I Am the Messenger and what is their importance?

Jay is the boy who offers to watch the Doorman while Ed plays in the sledge game. When Ed goes to get his dog, Jay and the dog are gone. He later spots Jay and the Doorman returning from getting a snack. A strange woman is talking to Jay. When Ed asks Jay what the woman was doing, Jay says the woman gave him a card to give to the man who owned the dog. Ed asks for the card, but Jay says that he is the one who owns the dog. Jay cons Ed into paying him $20 for his own dog and the card.