Sun Wukong

Sun Wukong is the first Monkey King and is known as The Great Victorious Fighting Buddha and the Great Sage Equaling Heaven. He is also Bikou's ancestor and Indra's former vanguard.

Appearance
Sun Wukong has the figure of a primary school child (at least a meter tall), covered in golden fur wearing a monk's cassock, a wrinkled, creased face and black skin. He is also seen carrying a staff-like weapon, smoking a pipe, wearing shades with a cyber design, and also donning prayer beads on his forehead.

Personality
Sun Wukong claims that he is a free geezer, not caring much for worthless things. Despite so, he would carry out the orders given to him by Indra and is shown to be wise enough to give advice to people. Sun Wukong may have a jokester personality as Yuuto Kiba once claimed that he can sense similarities in Sun Wukong's personality to that of Bikou's. In fact, Sun Wukong was known to be extremely mischievous in his youth as he's known to have once playfully caused a havoc so immense, that the Buddha had no choice but to imprison him underneath a mountain. He also hates Devils from the Old Satan Faction, claiming that they were the ones responsible for the destruction of his kin in the past. However, Sun Wukong's hate of the Devils is limited to their past generation as he believes that the current generation of the Devils is different and so, cannot be held responsible. He understands the value of determination and commitment and isn't hesitant to acknowledge others as shown when he complements Issei for defeating the Hero Faction and protecting his comrades even without the use of the Juggernaut Drive. Amongst the very few Gods, the few that he respects are Sakra,the Trimurti gods, Odin, Zeus, and the God of the Bible, as he generally hates evil beings, or Gods, that desire nothing but to conquer, destroy, or bring chaos to the world. He also has great respect towards the current leaders of the "Three Great Main Powers", and believes that they are strong and are capable of managing their own Factions very well.

History
Sun Wukong is a monkey that was born from a stone and acquired supernatural powers through Taoist practices. After rebelling against Heaven, he was imprisoned under a mountain by the Buddha. Before that had happened, he had earlier fought against the Bull Demon King, the one who manipulated him into rebelling against Heaven by killing his friends. After a massive battle, he successfully banished the Bull Demon King from Heaven after the latter attempted to overthrown and rule it. He later accompanies the monk Xuanzang Sanzang on a journey to retrieve Buddhist sutras from India while being accompanied by "Pigsy" (猪八戒 Zhu Bajie) and "Sandy" (沙悟浄 Sha Wujing), both of whom had offered to accompany the priest in order to atone for their previous crimes. The group encountered a series of eighty-one tribulations before accomplishing their mission and returning safely to China. There, Sun Wukong was granted Buddhahood for his service and strength.

After his ascension to Buddhahood, Sun Wukong eventually became Indra's vanguard. Shortly after the Khaos Brigade became known to the world, Sun Wukong was sent by Indra to fend off the organization, and succeeded in fending off many terrorist attacks, especially the ones led by the Old Satan Faction and the Hero Faction.

The Heroic Oppai Dragon
Sun Wukong is mentioned by Azazel in Volume 7, who informed Bikou that "the monkey" (referring to Sun Wukong) is currently searching for him (much to Bikou's dismay).

He makes his full appearance alongside Yu-Long at Kyoto in Volume 9, helping Issei and his friends during their fight against Cao Cao and the Hero Faction, who were mind-controlling Yasaka. As soon as he appeared, he effortlessly overwhelmed the Hero Faction, by defeating Siegfried in one shot, destroying the mist of Dimension Lost and blocking Cao Cao's True Longinus with a finger, all while claiming that they are still too young to challenge him, and forced the Hero Faction to retreat. He later advised Issei to use Pailingual on Yasaka to test if he can help her regain her consciousness, which it does. He then has a chat with Issei apologizing to him for the trouble caused by his kin and complimented the boy for choosing a different approach to harness the power of the Heavenly Dragon, instead of the usual Juggernaout Drive.

He was looking for Bikou until the latter calls him in Volume 12 to ask for his help in healing Vali Lucifer who is cursed with Samael's poison. Yuuto also asks him about Samael's poison in hopes of getting a hint on Issei's chances of survival to which Sun Wukong answers that the density of Samael's curse is very powerful, so there's a high chance of Issei's soul perishing alonside his physical body, since according to him, there is nothing more fragile than a soul that has lost its vessel. He then asks if Samael's curse was detected from Issei's Evil Pieces to which Yuuto confirms that there was none. Hearing this, Sun Wukong theorizes that despite the lack of his physical body, Issei's soul might be safe. He also gives assurance to Yuuto and the Vali Team that Indra won't rampage like Hades, before leaving the Gremory territory with Yu-Long to deal with the Khaos Brigade.

The Legend of Oppai Dragon and his Lively Companions
In Volume 16, Sun Wukong participated in the meeting for the formation of the D×D and was appointed as the sub-leader. He also proposed in training the members of D×D where they will be able to reach Ultimate-class strength and for the Longinus possessors to fight on par with God-class opponents.

In Volume 17, Sun Wukong helped train Issei and Vali to effectively use and not waste their powers. He, personally, sparred with Vali, with Vali not able to hit him at all, while a dummy in his likeness trained Issei to try and use the same amount of power ten times in a row.

In Volume 21, during the war against Qlippoth's army with the imperial beast in their control, Sun Wukong arrives mid-battle riding on Yu-Long along with Zhu Bajie, Sha Wujing, and Nezha, wiping out as many Evil Dragons and fake Scale Mails as they can.

Red Dragon Emperor of the Blazing Truth × White Dragon Emperor of the Morning Star: The True Dragon(s) of the Kuoh Academy
In Volume 22, Sun Wukong participates at the opening ceremony of the Azazel Cup, while also bringing Yu-Long, first generation Zhu Bajie, first generation Sha Wujing, and the Nezha Prince despite having decided to retire them. Sun Wukong noticed Mahabali glaring at Indra, he advised him that it won't be too late when he does fight Indra.

Powers & Abilities
Immense Strength: In his youth, Sun Wukong possessed an immense amount of strength. After his ascension to a Buddha, he's said to have become even stronger than before. Despite his advanced age, Sun Wukong is still extremely powerful, shown when he was able to overpower several members of the Hero Faction within seconds, a considerable feat as they were all Sacred Gear or Demon Sword Users. He was even able to block Cao Cao's True Longinus with a single finger, which is a tremendous feat considering the True Longinus is the most powerful of all the Longinus-class Sacred Gears. He is said to be able to fight and defeat Ultimate-class and High-class Devils with ease, without even showing the true extent of his strength.

Immense Durability: Sun Wukong is immensely durable to any attacks. He can easily tank most attacks without being hurt, as seen when he casually blocked Cao Cao`s True Longinus with just one finger. Although, it is stated by Wukong that even he would turn into ashes if he ever got hit by the attacks of both the current Heavenly Dragons.

Immense Speed: Sun Wukong is incredibly fast, being able to keep up with both Vali and Issei at the same time even with his replication ability.

Master Combatant: In the past, when the Khaos Brigade made themselves known to the world, Sun Wukong was sent by Indra to fend off the organization, and successfully managed to fend off several terrorist attacks with minimal effort. He is skilled enough to overpower Cao Cao, who is said to be the strongest human, and is most knowledgeable when it comes to combat skills. During his training session with Issei and Vali, using his replication ability, he was capable of fighting against both of them at the same time, with neither of them being able to land a hit on him.

Master Magician: Sun Wukong can cast a spell powerful enough to destroy the mist of the Dimension Lost. He is also shown to be able to remove very tough, thick, complex and powerful barriers and seals with ease, but was unable to do that in the past while he traveled with Xuanzang on account of the fact that he was still atoning for his sins at that time.

Senjutsu and Youjutsu Master: He is also a master of Senjutsu and Youjutsu, being able to easily rejuvenate Issei with a single tap from his staff. According to his descendant Bikou, Sun Wukong has complete mastery over Senjutsu and Youjutsu to the point that he can even be called a monster. His mastery of Senjutsu is shown when Sun Wukong used ki to cure Vali of the deadly Samael's poison.

Touki: As a master of Senjutsu, Sun Wukong can use Touki. Sun Wukong is described to possess an overwhelming amount of ki. Using this, he was able to easily remove Samael's poison from inside Vali, by controlling the ki inside the latter's body.

Equipment
Ruyi Jingu Bang (如意棒 Nyoi-bō): An iron rod/cudgel, whose size changes according to its wielder's wishes, that Sun Wukong obtained from the undersea palace of Ao Guang, the Dragon King of the East Sea. It is immensely heavy and has the power to change its size, multiply itself, and fight according to the whim of its master.

Jīndǒu Yún (筋斗雲 Kinto'un): Sun Wukong can summon a golden cloud that he can ride on.

Trivia

 * Sun Wukong is the Monkey King from the Chinese epic novel Journey to the West.
 * Sun Wukong is the first Buddha introduced in the series, the second being Xuanzang Sanzang, and third being Nezha.
 * His team name for the Azazel Cup is Journey to West in reference to him being the protagonist of that story.