Ouryuu Nakiri

Ouryuu Nakiri, born as Ryuuta Nakiri, is a first-year student and the secretary of the Student Council at Kuoh Academy. He is also the heir of the Nakiri Clan.

Personality
Ouryuu is shown to have a calm and friendly personality, as he appeared to the Occult Research Club in a polite manner. He is also very kind as he doesn't discriminate Devils and treats them respectfully. He holds a strong admiration towards Issei Hyoudou and considers him to be his role model.

History
Sometime before the series, Ouryuu was chosen by the Sacred Beasts, Huang Long, as its inheritor. He subsequently abandoned his birth name and took up his current name, becoming the heir of the Nakiri clan in the process.

The Legend of Oppai Dragon and his Lively Companions
Ouryuu was mentioned in Volume 19 as one of the new members of the Student Council and it's secretary under Xenovia Quarta.

Red Dragon Emperor of the Blazing Truth × White Dragon Emperor of the Morning Star: The True Dragon(s) of the Kuoh Academy
He makes his official appearance in Volume 22, where he appears to the Occult Research Club and deliver school related documents to Xenovia. He greets the members of the club and was quite aware that they are Devils and Angels. He says he's been given a mission from Ajuka Beelzebub to search for the remaining Longinus, Innovate Clear and Telos Karma. Ouryuu then bows his head to Issei and expresses his admiration for him for possessing the Boosted Gear of the Welsh Dragon and overcoming many dangerous situations.

Powers & Abilities
Immense Strength: Ouryuu is shown to be very strong as he is able to go toe-to-toe with Issei during training. Xenovia commented that he's in a different league among those with special powers.

Master Hand-to-Hand Combatant: Ouryuu possesses immense skill in hand-to-hand combat, as shown during his training session with Issei, an immensely powerful combatant.

Immense Speed: Ouryuu possesses impressive speed. When combined with his Touki, he is able to keep up with Issei during their training session. Issei even commented that Ouryuu could toy with a High-Class devil with his speed.

Dragon's Pulse: As the inherent possessor of the Nakiri Clan's Sacred Beast, Ouryuu, the yellow dragon that represents earth, Ouryuu is able to tap into the "veins" of ki that flow throughout the land. He is able to use this earth based ki to strengthen his own physical abilities to significant degrees. If Ouryuu fights in a location where the earth is rich, he will have a greater supply of earth based ki to draw from, therefore making him stronger.

Touki (闘気): Ouryuu covers himself in an aura of ki, drastically increasing his offense, defense, and speed. By using this in conjuction with his Dragon's Pulse ability, he can further enhance his Touki.

Trivia

 * In Chinese religion and mythology, the Ouryuu (Yellow Dragon) in East Asian culture is the fifth symbol completing the Sixiang (Four Symbols). This deity is the centre of the cosmos and it represents the element earth, the Chinese quintessence, as well as the changing of the seasons.