Nistro

Gauche is a character appearing in the Yu-Gi-Oh! ZEXAL anime. He is Dr. Faker's left-hand man and a committee member responsible for maintaining the World Duel Carnival along with Droite. Ultimately, his and Droite's true task during this tournament is searching for "Number" cards.

Appearance
He has a Duel Disk which looks a lot like IV's, but more of a fireball based design. He also has a Duel Gazer tatoo, like Kaito Tenjo, III, IV and his partner Droite.

Personality
Opposite to Droite's cold-blooded personality, Gauche is a very high-spirited person evident to how excited he got during the opening ceremonies of the World Duel Carnival.

He also seems to take his job less seriously as when investigating mysterious Duels within the tournament, he joked about how some of the Duelists were defeated whilst Droite maintained a calm manner whilst investigating.

This tends to cause frequent arguing with his partner, but they actually get along better than they initially appear and their dueling styles complement each other well. It also seems Gauche values Droite (or at least his co-workers in general) highly, as during their duel with Yuma he activated a card that served no other purpose than to take the hit for Droite. It otherwise didn't change the outcome of the duel at all.

Gauche seems to love Dueling, punishing heavily anyone that dishonors Dueling. As a member of the committee, he is very severe when punishing a cheater, to the point of physically injuring the participant or forbidding him/her of Dueling in the Heartland City for the rest of his/her life. After his defeat, he formed a friendly rivalry with Yuma and Astral.

He also has a habit of saying "nori" in each of his sentence.

Etymology
Gauche" means "left" in French. This may be a reference to the fact of him being Dr. Faker's "left hand" while Droite is the "right hand".

World Duel Carnival
During the opening ceremonies of the World Duel Carnival, Gauche along with Droite and Mr. Heartland kept watch over various parts of Heartland. Seeing the amount of Duelists excited Gauche, but he was quickly scolded by Droite who told him to be more professional. He then argues with Droite but is stopped by Mr. Heartland. Kaito Tenjo arrived, with Gauche joking about how quickly Kaito responded to Heartland's summons. Kaito gave him an annoyed look in response.

Gauche and Droite investigated incidents during the World Duel Carnival, such as Housaku Yasai's Vegetable Death Matches. During that time, he wore a blue Duel Gazer. They are responsible for eliminating Duelists who break the rules of the tournament, now Dueling with a tattoo-like Duel Gazer akin to Kaito's. When Flip does so, Yuma Tsukumo intervened and Dueled them in Flip's place.

Their combination overpowered Yuma and drastically lowered his Life Points. On an attempt to turn the Duel around Yuma manages to Summon "Utopia", surprising Gauche and his partner as he holds a "Number" card. When Droite Summons "Photon Butterfly Assassin", Yuma identifies them as being affiliated with Kaito, and they learn that he has Dueled Kaito. Yuma gave up hope when they reduced him 100 Life Points, but Astral returned and was briefly visible to everyone watching the Duel. Droite and Gauche identified him (Astral) as the "original Number". Astral helped Yuma execute a winning move and Yuma attacked Droite. Gauche defended her with "Bouncer Guard", resulting in him losing instead of her. After the Duel, Gauche asks Droite not to tell Mr. Heartland about Yuma because he wants to defeat him himself before Kaito does.

After Haruto Tenjo disappears from Heartland Tower, Gauche and Droite went to look for him via a helicopter. After finding him, Gauche blames Yuma for kidnapping him and when he tries to take Haruto back, he creates a powerful energy to force Droite and Gauche to retreat, when they return, Haruto, Yuma and Tori have disappeared.

Having found that Haruto has disappeared, Kaito contacts Gauche and Droite in order to find out what has happened. Gauche thought it would be best to ignore Kaito, but Droite listened to what he had to say, and then told him the area of the city where Haruto was last seen. After Haruto is abducted by V, Gauche and Droite manage to find Yuma in order to question him of Haruto's whereabouts. Unfortunately for Gauche, Yuma kicks him in the crotch in order to escape, causing him immense pain. He then regains his power and goes to attack Yuma again, but is stopped by Kaito. After discussing about what to do, he along with Droite decide to leave the job to Yuma and Kaito. They then get back into their helicopter and fly away.

Deck
Gauche plays a Bouncer Deck focused on Summoning high-Level monsters in order to punish and relentlessly attack the opponent, reflecting his fiery personality. His Deck is spearheaded by "Photon Streak Bouncer".