Chumley Huffington, known in Japan as Hayato Maeda 「前田隼人, Maeda Hayato」 and known in the Philippines as "Japoy Madaea", was initially a Slifer Red Duelist with an extremely pessimistic outlook but gradually grows to become a respected card designer for Industrial Illusions.
Chumley's character design was overseen by Kenichi Hara. His usual outfit consists of the standard Slifer Red uniform, though its colors are inverted to include a larger section of white than red. His face, build, and hairstyle were made to resemble a koala. As conceived, the character was very muscular, but his muscle tone is removed from the English version to make him appear obese. He carries an Duel Academy-issued Duel Disk on his left hand.
In the English dub, Chumley is obsessed with grilled cheese sandwiches. It is said at one point he creates a Grilled Cheese Spell Card. His obsession with the food leads him to use phrases such as "lischus" and "not lischus" as positive and negative assurance respectively, the words being derived from "delicious."
In one episode, it is implied that he speaks French.
In the original version of the series, Chumley has the same power to hear and see Duel Spirits that Chazz Princeton and Jaden have, although he is not totally aware of it. While "Des Koala" is pictured with him several times in as his spirit partner, this information is omitted entirely in the dub.
Chumley was forced to retake his freshman year after he failed his first time around. His best friends, Jaden Yuki and Syrus Truesdale, come to Duel Academy, and encourage Chumley to gain more confidence in himself.
Throughout the series, Chumley participates in only two Duels: the first against his father, Mr. Huffington, and the second against Dr. Crowler. His father believed that his son's efforts at Duel Academy were wasted and that he would be better off leaving. To put an end to the conflict, Chumley struggled valiantly against his father's special tactics, but ultimately lost. Despite this, he allowed his son to continue his studies, as he saw that Chumley had actually learned something, and that his friends would always support him.
Maximillion Pegasus offers Chumley a job at Industrial Illusions as a card designer nearing the end of the first year after he wins a card-design contest by creating "Ayers Rock Sunrise". In order to determine whether or not he will be permitted to leave the school, Crowler Duels with him in one final test. Although Chumley manages to hold his own, even getting the chance to play the first card of his own creation, "Ayers Rock Sunrise", he is again defeated. Crowler, however, lets him move on regardless, impressed by how far in his studies he has come.