Yuma appears as a young boy with tan skin, red eyes, and black and red spiked hair that points out and upward. He wears a red Duel vest with a white hood and a purple tanktop with a green "D" symbol, standing for "Duel". Yuma also wears white pants with designs of three orange moon crescents attached to one another with yellow outlines at the bottom, a white brown-stripe belt, and black with blue streaks shoes with white straps.
At school, he wears a white shirt with red-lined sleeves and collar, a red tie, blue pants and brown shoes. In his nightwear attire, he wears a red-white t-shirt grey pants, and sometimes green slippers, but Yuma mostly goes barefoot around his house.
Yuma had same dream again about the mysterious door demanding him that if he opens this door he will receive a new power but in compensation they will lose their most important thing. Yuma thought about his most important thing as the key reacting making the ground below him suddenly crumbles away causing him to fall into a big hole. Later Yuma witnessed as his friend, Bronk Stone dueling Shark and lose the duel getting his deck taken. Yuma tried to stop them, but end up with Shark breaks his key from his neck and throwing away the pieces. Then he makes the proposal to Yuma to win back Bronk's deck, if he defeated him in a duel. The day before the duel, Bronk gave Yuma the lost piece of Emperor's Key and built so well his confidence again. On the day of the duel,Shark quickly took the lead and pulled Yuma already in the second round for half his life. Yuma's amateur skills seemed to have no chance against Shark. Shark taunted him to give up, Yuma urged that he will not give up because he has always believed in himself.