Yahiko

was a shinobi from Amegakure and founder of the original Akatsuki. His body acted as the Deva Path of Nagato's Six Paths of Pain.

Background
Yahiko was orphaned during the Second Great Shinobi World War, and, thus, he started fending for himself, stealing food from others. He later encountered Konan, also an orphan, and the two began to work together to survive. After this, Konan brought another orphan, Nagato, and his dog, Chibi, into the group. At first, Yahiko was upset that she was bringing more people, but he later accepted Nagato and Chibi into his gang. Angered by how unfair the world was to them, Yahiko declared he would become a god to end the fighting.

The three eventually encountered Jiraiya, who looked after them and taught them basic ninjutsu. At one point, Nagato saved Yahiko after an Iwagakure chūnin attacked them. Afterwards, Yahiko vowed to become strong enough to protect Konan, Nagato, and eventually all of Amegakure.

During their time with Jiraiya, he created a defense system to protect themselves should enemy ninja find their hideout composed of four planks, each with one red side and one white which had a frog picture on it attached to a part of a wall of the hideout they shared at the time with their names underneath it. The purpose of the planks were so that when they were in the hideout, they turn their planks to the red side and they leave, they flip the plank their plank to the white side, so when a plank's on the red side and the person's not in the hideout, it means they could have been captured by the enemy and when a plank's on the white side and it appears that the person's in the hideout, it could mean that an enemy has transformed into said person and has infiltrated the hideout, along with a trapdoor hidden among the floorboards leading to an hidden room and emergency escape route he left just in case. Yahiko asked why Jiraiya always tried to force his frog ways on them and that they only tolerated it because he was the "Frog Sage". Konan then explained the possible reasons for implementing a code like that which Jiraiya praised her for. He then declared that it was time for training to which Yahiko responded to enthusiastically claiming that one day he would get stronger and change the country before running outside. After hearing his words Konan blushed at him to which Yahiko responded with a pervy smile reminiscent of that of his master's.

Some time after Jiraiya's departure from Amegakure, the three gained a reputation as a talented shinobi team. Still desiring to create a world of peace, Yahiko and his friends went on to become fully fledged Ame ninja, and gathered many supporters who shared their hope to save their village and the world. Yahiko eventually united them together with the name of Akatsuki, an idea Madara Uchiha claims to have given him. Akatsuki spread their beliefs to stop war without violence, and news of their actions would reach Jiraiya from time to time. When their group became too big, they were forced find another hideout, and leave their current one where they once lived with Jiraiya. When they were about to leave and flip over their "Hop-In" planks, a ninja squad attacked the hideout creating an explosion which resulted in a hole in the roof which they used to infiltrate the hideout. Yahiko (after Konan flipped her plank and just before he was about to flip his), noticed the attack in time and used the escape route just before ninja entered the hideout.

Their group became so well renowned that even the then leader of Amegakure, Hanzō, started to view Yahiko and his supporters as a threat to his power. Working with Danzō during the Third Great Shinobi World War, they captured Konan and forced Nagato to choose to let Hanzō kill Konan or for Nagato to kill Yahiko himself. Without hesitation, Yahiko drove himself into a kunai that Nagato was holding. With his final breath, he told Nagato to continue their mission of finding peace.

Personality
Yahiko's personality was similar to Naruto's. His dream was to be a leader of his village, and he never gave up no matter what. When he was alive, Yahiko had a strong "eye for an eye" philosophy. He hated the way Amegakure was looked at by the rest of the world, and hated what it had become. He was defensive of the village, saying that it was his dream to stop the endless rain, which he compared to tears, and protect the nation's citizens. Yahiko wanted to become the ruler of the world so there wouldn't be any more wars. Many of these traits were adopted by Nagato after Yahiko's death.

Among the three Ame Orphans, Yahiko seemed to act as the leader of the group. It was Yahiko who first approached the Sannin to ask for food, and was the first to ask Jiraiya to teach them ninjutsu. He also seemed to act as an older brother for Nagato and Konan, reminding Nagato to not cry and to act more manly (although Yahiko was the one who cried when Jiraiya left them). He also wished to become stronger so as to protect Nagato and Konan. He had faith in Nagato, when he got older. Yahiko was willing to commit suicide rather than endanger Konan's life, displaying a very high level of loyalty to those he cared for. He had romantic feelings for Konan.

Abilities
Yahiko had the ability to use water-based jutsu, although the only example of this shown in the series was Water Release: Violent Water Wave, in which he was able to shoot a jet of water from his mouth. The Deva Path also had the ability to control rain, presumably Nagato fulfilling Yahiko's desire of "stopping the endless tears". The fact that he was seen carrying a large sword in the flashbacks implied that he was skilled in kenjutsu. He also had good leadership skills, he was respected by all the Akatsuki members of his time, and although he viewed Nagato as the bridge of peace everyone else however viewed him to be the true bridge of peace not Nagato.

Deva Path
Nagato, using his Rinnegan and chakra receivers, incorporated Yahiko's body into his Six Paths of Pain technique. As the Deva Path, Yahiko's body had acted as Pain's main body, it being the one he most commonly used and spoke through. The Deva Path was held in higher regard during combat, some of the other bodies being sacrificed to ensure its survival. It has a wide variety of ninjutsu, the most prominent being able to manipulate gravity. Following the Deva Path's defeat and Nagato's death, Konan took both of their bodies back to Amegakure.

Confining the Jinchūriki Arc
After Madara captures Konan, he gets info where she had hidden Nagato and his Rinnegan. Then he marches to the place which turns out to be the house where the Ame trio had previously lived with Jiraiya. Yahiko's body is seen next to Nagato's body - his eyes are closed and there are no holes made earlier by penetration of chakra rods. He is laid on paper flowers made by Konan.

Trivia

 * Yahiko shared his birthday and blood type with his former team-mate, Konan.
 * Yahiko's eyes are shown to be a light blue in the manga. In the anime, his eyes are depicted as brown.
 * When split into its separate kanji, means increasing, while  means boy.

Quotes

 * (To Jiraiya) "If we're gonna "understand" each other, first we gotta make 'em suffer like we're sufferin'!"
 * (To Nagato) "I'm gonna rule the world!!"
 * (Thinking outloud) "If war is going to continue - I will become the God of the world!!"
 * (To Konan) "Our country's still crying... still enduring all this pain. I used to hate it so much... but now I want to save it from the bottom of my heart. Its a big crybaby, like I used to be... I can't just leave it."
 * (Last words to Nagato) "You and Konan... You've gotta stay alive somehow... You're... the savior of... the world... You... can... bring... real--"