Manager of the RPG Hobby Trading Card Shop
This unnamed clerk runs a small RPG and trading card shop in Domino City. The place became notable as the official distributor for the new Duel Disks during Battle City, which made it a natural hub for tournament hopefuls.
Behind the scenes, though, the manager was working with the Ghouls—a group hunting rare cards. Whenever someone registered for Battle City with a valuable card in their deck, the manager would tip them off. Most infamously, he rigged Jonouchi Katsuya's ranking, claiming it was a "technical error," specifically to flag his Red-Eyes Black Dragon for theft. After Jonouchi left the shop with his friends, the manager didn't waste time calling Marik Ishtar directly and asking him to send Rare Hunters after the kid.
The scheme worked. Marik dispatched three Rare Hunters to target Jonouchi in Domino City.
In the manga, Dark Yugi eventually caught on to what was happening and stormed the shop to confront the manager. Instead of finding him, though, he ran into Pandora waiting inside.
Content compiled by AnimeList.moe from publicly available sources.