Iruka Umino

is an instructor at the Ninja Academy, characterized by the distinctive scar across his face that he has had since childhood. The name "Umino Iruka" can be taken as "umi no iruka" ("sea dolphin").

Background
Twelve to thirteen years ago, the Nine-Tailed Demon Fox attacked Konoha, killing many people. Iruka's parents were still out fighting the Fox and were killed. Iruka was dragged back for protection by an unknown ninja but wanted to stay where he was. After it was over, everyone in the Ninja Academy made fun of him and made him feel just like Naruto Uzumaki. He was always near the K.I.A. (Killed in Action) stone monument where his parents were listed and always cried. The Third Hokage would watch him and once it is seen he cheered Iruka up. Mizuki was a close friend of Iruka back then and usually made him feel better but he was just acting to get the Hokage approval.

Personality
Iruka has a huge like of Ramen, especially Ichiraku Ramen. He is shown to be quite strict when all the Rookie 9 were in Academy however inside is revealed to have had a life just as miserable as Naruto's after the attack of the Nine-Tailed Demon Fox.

Introduction of Naruto
His parents were killed by the Nine-Tailed Demon Fox when he was younger, though he holds no hostility towards its container, Naruto Uzumaki. In fact, Iruka is one of the few people at the start of the series who values Naruto as a person, being able to relate with Naruto's methods of trying to gain attention. Because he, like Naruto, was forced to grow up without parents, and was socially isolated as a result, he can relate to Naruto in this regard as well and has assumed the role as Naruto's father-figure. Once Naruto becomes a ninja Iruka starts to underestimate Naruto, and as such become overprotective of him, though he in time discovers that Naruto has all the markings to become a great ninja.

Chunin Exams
Iruka was chosen as the messenger for the Chunin Exams. He would greet those who passed the second phase and appeared from a Heaven and Earth Scroll. The first team he met was Team Kakashi. He introduced the writing about putting Heaven (mind) and Earth (body) together. Naruto, to his excitement for passing worried Iruka because of the earlier immaturity but Naruto went on saying that he had changed ever since he got his forehead protector. This made Iruka feel better.

Mizuki Strikes Back
Tsunade orders Iruka to go on an S-Rank mission. He, along with Naruto and Pakkun, meet Mizuki. As Naruto and Pakkun take care of Fujin and Raijin, Iruka goes on to a forest-like area to fight Mizuki who now has unbelievable strength. Mizuki has improved so much that Iruka almost has no chance against him. They later go to a dark place to fight where Iruka is beaten similar to how the Third Hokage fought the First and Second Hokage with the Bringer-of-Darkness Technique. Iruka concentrates more and finds Mizuki, who later esapes. They then meet Mizuki's wife, who reveals that earlier he stole the scroll for the good of Orochimaru. Then after Mizuki uses a formula to activate the animal cursed seal, they finally find him again and battle Mizuki in his Cursed Seal Level 2 form. They then notice that Mizuki is decreasing in speed and use that as an advantage. Iruka uses his headband to direct Naruto into using the Rasengan in the correct direction, which they injure Mizuki and win the battle. Tsunade and the Medical team then recover Mizuki. Iruka offers to treat the group to ramen, however Tsunade says that he and Naruto need to recover first.

Abilities
Little is known about Iruka's abilities, but he is clearly proficient in the basic ninjutsu and genjutsu, seen when he disguises himself as an enemy ninja and menaces Team 7 as a pretest for the Chunin Exam. The anime filler episodes show Iruka using, which consists of setting an array of exploding tags and, once the target has entered, setting the tags to detonate if the target moves. Because this only applies to the target, meaning others can freely enter the array without harm, it is possible that Iruka is skilled in this area.