Ryuji Otogi is a character in the Yu-Gi-Oh! manga. This is the original depiction of Ryuji Otogi, known as Duke Devlin in the English anime.
Dungeon Dice Monsters
According to his father, Ryuji was born in order to fulfill his father's revenge on Sugoroku Mutou. Sugoroku had defeated Mr. Otogi in the Devil's Board Game, causing him to age 50 years in one night.
Ryuji was transferred to Domino High School, where Yugi Muto (Sugoroku's grandson) goes to school. His father used this as an opportunity for Ryuji to defeat Yugi and fulfill the family's revenge.
Ryuji became immediately popular at the school, impressing girls with his dice tricks. Jonouchi grew jealous and confronted Ryuji, who challenged him to a simple card game. Dark Yugi saw how the probability favored Jonouchi losing, despite looking like a 50-50 chance. Dark Yugi then challenged Ryuji to a slightly altered version of the game, where a player has an even chance of winning or losing. To Ryuji's annoyance, Yugi wins twice in this game.
While Yugi and his friends are browsing the Otogi family shop; the Black Clown, Ryuji's father sneaks some merchandise into Yugi's pocket and accuses him of stealing it. After Yugi is taken away by store security, Mr. Otogi takes his Millennium Puzzle and has him put in a room with Ryuji, where he must face him in a game of Dungeon Dice Monsters.
Without the Millennium Puzzle, Yugi was unable to change to Dark Yugi, but managed to do alright in his game against Ryuji, despite having never played before. Mr. Otogi became disappointed in Ryuji's performance and smashed the Millennium Puzzle.
Ryuji got Yugi in a tight spot again, but Dark Bakura talked Yugi into continuing. Yugi defeated Ryuji, who was moved by the game. Ryuji told his father that he cannot make himself hate Yugi and cannot take revenge on him. Mr. Otogi seized Yugi by the neck, with the chain from the Millennium Puzzle and dragged him into another room, telling Ryuji that he failed and no longer has the right to live. After his father's secret room became engulfed in fire, Ryuji took his father out of the way while Yugi re-completed the Millennium Puzzle and then was rescued by Jonouchi. He then became a of good friend of Yugi's.
Ryuji followed Honda to the hospital, to take care of Jonouchi's younger sister, Shizuka Kawai who just had her eye operation. He helped Honda take care of Shizuka, and met Mai Kujaku. He witnessed the finals.