"Original Sin" opens with a description of the protagonist's first encounter with the demon. The protagonist, who is now known as "Rouste," is a young man who has just returned from a day of work. He has come to retrieve his dog, "Puxe," who has been sold to a gang. He tells the protagonist that he is not interested in "demon card," "gangs," or "your dog race." He is only interested in getting his dog back. When the protagonist realizes that his dog has been killed in the battle, he realizes that he has no choice but to leave the scene. He asks the protagonist if he is from "Garage Island," and the protagonist tells him that the city is under the control of the demon, "Haru." The protagonist tells the story of how he came to be in the city, and how he had to stay behind to watch a dog race. He says that he hopes that the dog race will be over soon, and that he will have enough money to buy him a ticket to the next race.