Haga promised the boy a rare card if he could sneak the card "Parasite Paracide" into Jonouchi's Deck. After trailing Jonouchi for over an hour, the boy finally got a chance when Jonouchi entered Beef Buster and took off his Duel Disk at the manager's request. He immediately snatched the Duel Disk and ran out of the restaurant, with Jonouchi in hot pursuit.
Eventually, Jonouchi caught up to the boy, but not before he successfully infected Jonouchi's Deck, as per Haga's instructions. The boy then spun a story to Jonouchi about how he was a Battle City contestant that was defeated in his first Duel and had his own Duel Disk and Deck stolen by his opponent. Jonouchi fell for the story and let the boy go, telling him to find the thief so he himself could Duel him and win the boy's Duel Disk and Deck back.
The boy met up with Haga and told him that the plan was a success. Haga gave him a common "Pillroach" card as compensation, making him protest that Haga had promised him a rare card. In response, Haga sprayed a can of insecticide in the boy's eyes.