Izō is a black-and-white Siberian Husky/Alaskan Malamute mix with blue eyes. His neck and muzzle are dark-colored and he has small white dots on his forehead.
In Ginga Densetsu Weed anime, he has olive-colored eyes and the white parts of his coat are very light brown instead of white.
He's very loyal to the Ohu Army and through his adventures with Orion in GDWO, he is very caring about his family wishing to avenge their death and has grown fond of the young pup wishing to be his guardian.
Izō is first seen hunting a bear with his brothers, but gets injured. Shigure, who was on a mission to gather soldiers from Mutsu, interferes and takes out an eye from the bear. Kisaragi's sons are wary of the Kai mix, but Izō tells them to show more respect.
When they arrive at Futago Pass, Genba was roaming with Tōbē. The Mutsu brothers attack, and Izō gets badly injured by Tōbē. He is taken to a safe place by Akame, and does not participate in the battle from then on. Throughout the manga and anime, Izō is mostly in the role as a background character like his brothers.
Izō and all the Mutsu brothers are sent to Hokkaido with the Ohu soldiers to help the dogs under Hakuro, who were getting invaded by the Russian Army dogs. Nine of his brothers were killed in battle, but Izō survived.
Izō is first seen in the Orion manga with his brothers when they encounter with Orion's little sister, Bellatrix. He sends his brothers out to find help when an unknown dog jumps out of nowhere and slams in Izō, grabbing Bella. He and his brothers vehemently kill the dog that tried to kidnap Bella. After the battle, he takes off with Shirozaru and Sasuke to help Orion's new comrade, who is in danger. They fight off many of the dogs, some getting badly injured or even killed.
Later, as he meets Orion, he is still with Sasuke and Shirozaru. As Orion runs past him, he moves quickly and grabs him by the back of the neck, knocking him out. He takes him to the shed, where Orion's little sister Bellatrix waited. Izō and his brothers, along with Orion, and his comrades Heizou and Tyson, take off to search for Ohu survivors.
He goes to find his mate Sayako and his pups, only to find all of them dead. He found his father, Kisaragi dead in the underground cave, and he sadly screams loudly.
His last pup, Kuranosuke, only survived long enough so he could tell Izō what happened, and who caused the murder of Izō's father and pups. He says that the Kurohabaki Clan, led by a white dog, killed them. After that, Kuranosuke slowly dies.
Izō howls loudly as tears run hard down his face. After running a little while longer, Izō and his brothers become very tired and they collapse onto the snow. Izō looks up at Orion and says: "You have become a great comrade of mine." After hearing that, Orion jumps onto Izō, hugging him. Izō is shocked at first, but then returns the hug. He later leaves with his brothers, leaving Orion behind.
He and his brothers finally come across Masashige wishing to avenge his family, the dogs get into a fight. When Izō gets into trouble he sees Orion coming to the rescue and manages to get the white german shepard off him. Then he sees the pup trying to attack Masamune and once he did Masamune sends Orion rolling down the mountain and he catches Orion and tries to escape.
Then, they end up being chased by Masashige and his group and they get into another fight however it causes an avalanche causing everyone to be buried. Izō digs himself out to discover he lost two his brothers.
He and everyone mourns in the death of Izō's family and comes across Ishibuchi Jirōta and his pack. Izō kills him in an instant, then he is surprised to see the rest of Heizo's family safe and sound. Then, he follows Orion to discover that he found ninja dogs in the trees and finds out they were with Tesshin.
Tesshin then shows Izō that he's been teaching other dogs the Battouga, he watches over Orion's training with the others. Then when it seems that Shuto got hurt Izō rushed to the scene but sees that he's okay and Izō was impressed with the young pup's training. He leaves to find the Kurohabaki Clan's hideout.
Along their travels they come across a dog trying to eat a boar but the boar is still alive but due to Izō and Orion's quick actions he was quickly saved. Then, he tells them of the Sanada Clan a group of dogs that might be able to help and leaves for Unsai's tree. He and the others are attacked by Unsai's group after Izō explains the situation Unsai apologizes and shows Orion his home.
Izō is also seen in the final battle against Masamune Kurohabaki when Orion tries to move in to kill him he is stopped by Weed. As Izō and the others listen Orion's speech they were too fearful to move but Izō took his speech to heart crying with his head hung over.
Just Orion was starting to leave Izō wanted to come with him but his stopped Kyoshiro asking what is he thinking. He responds by saying that he will becomes Orion's guardian he also says that even though Orion is tough he's still a child and needs support to which Gin gives his thanks. Sirius and Bon asks Izō what's he thinking but all that he said is that Sirius will be Ohu's successor and if he leaves Izō knows the army wouldn't change and that he protect Orion no matter what.
His brothers ask him that they'll come with him but Izō politely refuses saying it will be okay. Weed expresses his thanks to Izō then, he says he should be the one to thank him.
Then, Izō and the others watch Masamune commit suicide in a horrible way.
Izō is present when the son of Akakabuto, Monsoon, attacks their land. He fights bravely but as with the others is badly injured and placed in a makeshift prison by the bears who have now claimed Ou for themselves.
Many days later, Izō and the rest of the dogs are rescued by Mole and his group. Barely able to walk due to injuries and being cramped in the prison for so long.
Shortly after, Izō and other Ou army are resting in the grass during a storm. As they rest, the Koga Elder begins to succumb to his wounds and old age, dying in Tesshin's arms. Blinded by rage, Tesshin sets out to find Monsoon and Izō follows, despite the fracture in his hind leg.
Izō arrives at the battlefield long after Tesshin, and is determined to fight. As he rushes past Orion and the others, they notice he has a stomach wound and his intestines are showing.
Despite his injuries Izō wanted to fight Monsoon, as the bear comes right for him Orion distracts Monsoon while Sirius carries him to safety. But, he tells the silver akita to not get in his way and that his injuries tell him that he's good enough.
Izō asked Unsai for the sickle saying that he can't fight Monsoon without it and because of his injuries he will never heal.
Izō takes sickle from Unsai, tells Monsoon it's his turn and talk to Unsai that he shouldn't have to do anything dangerous and it's Unsai's duty to make sure Orion and others have a future. Izō yells at Andy not be stupid and that he can take it when he's dead. Izō tells Andy that he need to die for Andy and the others sake. Izō cuts Monsoon's paws and tells him that his spirit is not broken yet, Monsoon is about strike his claws at Izō and tells Monsoon to remember his face that he's Izō of Hakkouda but Orion save him from Monsoon. Orion tells him to give him sickle and should go. But the husky tells Orion and Sirius that he can leave him with sickle and there's plenty of old guys who have to die.
Izō tells them that they need to stay out of his way but Andy says to give him sickle and that he can't handle the sickle in his current state. Izō told him don't give him that. He's not dumb enough to be talked down by them yet. He and other dogs hear from Sirius that Monsoon is angry because he doesn't understand dogs and that this isn't the way to do it. They don't need the sickle and should be healing Monsoon's wounds before they hurt him. Izō tells Sirius that how long he gotta be naive and that he can't live in the wild if he kept thinking like this. He knocks him off on the ground, and tells Sirius that he should not speak like fool. Gennai grabs the sickle from Izō and tells him that he got serious injuries, and thinks he can win with his spirit. Izō is asked by Unsai if he wants to die with no shame as an Ouu Soldier. Gennai tells Izō that as long as he has the sickle, he can die as a member of the Ouu army. Izō wants Gennai to give the sickle back, but he tells Izō that he may be giving up his own life.
Izō and the others tried to use up what was left of their lives. Izō tells Orion to come back and was frustrated, and on the verge of dying in anger.
Sometime later, Izō witnesses that something bad has happened to Akame, as humans come closer he wonders what Daisuke and Hidetoshi are trying to do. Izō then was found by the hunters; Izō says that if the humans try to touch him, he will bite them, until Kyōshirō comes and tells him that they are trying help. Knowing that, he lets the human take him away with the hunter also calling him adorable. Kyōshirō then tells him not to bite the humans and he replies back as he's the one to talk because he has to take care of everything, as he is taken away for treatment along with Akame.
After Orion's second departure, it seems Izō is recovering well with the others and he hears Akame mention of the secret arts of fanged ninjas and that when it comes to mastering the techniques takes great discipline of the mind and body and that Akame himself took ten years to master.
- He and his brothers are called Alaskan Malamutes several times in Ginga Densetsu Weed, despite the fact that their father was mentioned to be Siberian Husky. However, in a newly published book, he is confirmed a Malamute.
- His mother may likely have been a Malamute, explaining the breed difference.
- He appears more like a Siberian Husky, as he has a straight tail whereas Malmutes' tails are curled like Akita Inus' tails.
- His name is based on an assassin in the Bakumatsu of the late Edo period named Okada Izō (岡田 以蔵).