Kujirada acquired a Hidden Character Digital Pet. It had certain characteristics that normal Digital Pets didn't have, including a longer lifespan. However it would keep him awake at night, demanding more food. The pet developed a personality of its own and considered itself to be Kujirada's master. It grew tired of the food Kujirada was giving it and demanded it be given better food and would make Kujirada famous in return.
Meanwhile, Yugi, Jonouchi and Anzu had also gotten their own pets. Yugi connected his pet, U2, with Jonouchi's pet. Jonouchi's pet initially bullied U2 by kicking him, but became friends afterwards.
At school, while Jonouchi was out of the classroom, Kujirada connected Jonouchi's pet with his own, allowing his pet to eat Jonouchi's. As the pet demanded more food, Kujirada swiped Anzu's pet, Peachy and fed it to his too. Still hungry, the pet demanded more food, so Kujirada tried feeding U2 to it. U2 tried running away, but Kujirada's pet caught up to him and lifted him towards his mouth. However using the data it incorporated from its connection with Jonouchi's pet, U2 changed to a more powerful form and was able to fight back and kill Kujirada's pet.