Ogata has black hair that is shaved at the sides in an undercut fashion, a thin beard, and dark eyes. He sports a suture scar on each cheek, acquired after he fell from a cliff and broke his jaw while running from Sugimoto.
He wears a navy-blue uniform with red and yellow details, along with white gaiters, and he is often wearing an off-white button-up cloak and hood.
Ogata is analytical and ruthless, a proud sniper who is used to examining things from afar and evaluating circumstances in order to best take advantage of them. Even when at a disadvantage, Ogata keeps his nerve and takes the most advantageous course of action.
Moreover, he doesn't hesitate to kill, although he is aware that wanton slaughter is counterproductive. He considers patricide to be a rite of passage to adulthood.
He generally acts sociable and polite. Whenever he meets someone, he will act civil, though he may openly look down on some people. Ogata also likes to snark about any perceived absurdity.
He has a habit of slicking his hair back. He seems to be a very proud man as he would attempt to do a task that someone says would be difficult for him and puffs his nose when praised.
Ogata is the son of Lieutenant General Koujirou Hanazawa and his mistress. His father was the former leader of the 7th Division who committed seppuku after a war. Ogata boasts a skilled military lineage, including his grandfather, who also served in the army. Some time as an adult, he joined the 7th Division, which Tsurumi presumed was to get revenge on the military for pushing his father into committing suicide.
Ogata took part in the Siege of Port Arthur where he fought in the Battle of 203 Hill along with his division and the other divisions of the Imperial Japanese Army. When Genjirou Tanigaki was able to retrieve Kenkichi Aoyama's body and tried to speak to him, Ogata told him that there is nothing he can do for Aoyama as it looked like his eardrums have burst. Afterwards, the Japanese army were able to take 203 Hill with Tsurumi claiming victory.
In Meiji 38 (1905), Ogata also fought in the Battle of Mukden and witnessed Tsukishima attacking their superior, 2nd Lieutenant Tsurumi for having lied to him. Tsurumi then told the 7th Division soldiers who had gathered due to the commotion to leave both him and Tsukishima alone to talk.
(From chapter 70 onwards)
After formally allying himself with Hijikata's group, the group as a whole are next seen resting at a cabin. Ogata begins to mock Hijikata and his ambitions before talking about Noppera-Bou when Hijikata doesn't say anything. He talks about how Noppera-Bou killed seven Ainu men, and their customs about treating the dead as he questions his motives. He listens to Hijikata saying that Noppera-Bou might be a partisan from the far east of Russia and about how there are political and economical movements in that area. Ogata then speculates that Noppera-Bou wanted to use the Ainu gold to fight for independence, but failed to export it, which led to the situation that his party is currently in. (70)
Ogata later travels to Yubari with Ushiyama, but got split up from him. Though he is able to locate the Edogai workshop. He manages to kill Maeyama by sniping him through a window, which catches Yasaku Edogai's attention. As he prepares to head in, he notes that Sergeant Tsukishima often takes long baths which should give him plenty of time to find the taxidermist. In the store, he finds some materials on the ground and realizes what they are for, before noticing that one of the stuffed animals had gone missing, which means Edogai had escaped. He is suddenly confronted by Tsukishima and the two have a gunfight before Tsukishima leaves to find Edogai. As he is about to leave himself, Sugimoto and Shiraishi comes into the store, but he is able to silence the latter to lead Sugimoto away, so that he can find Edogai. He is able to locate the taxidermist preparing to shoot him, but Tsukishima comes rolling in a mine cart and grabs Edogai to flee, much to Ogata's surprise.
Ogata hops into a mine cart and stays behind so as to let Tsukishima and Sugimoto destroy each other, which would make it easier for him to grab the skins. In the middle of his fight with Sugimoto, Tsukishima triggers a switch that causes Sugimoto to go down a different path. Afterwards, Ogata shoots at the switch to put him on the same path as Edogai and continues to chase after them. As he runs by a couple of miners, he hears them screaming that they had just lit a dynamite and attempts to stop his cart by pushing his rifle onto the ground to avoid the blast. He gets out of his cart and tries to push it to continue the chase, but then he smells something in the air, to which the miners proclaim that it is a gas outburst, which can make the dynamites more powerful. Ogata is caught in the explosion and attempts to get to safety, but is caught by a windblast which would cause another explosion. Despite his injuries, Ogata continues to crawl to escape the mines before it is closed down.
As he makes his way out of the mines, he spots Edogai's body trapped under a pile of logs and rocks but is shouted at by a miner who tells him he is going the wrong way. He is able to leave the mine and get some fresh air whereupon he spots Ushiyama with Sugimoto's group. He offers to take them along to explain the situation and took them to the Edogai store. There he revealed the bodies that were skinned in order to make the fake tattooed skins much to everyone's shock. He confirms that Edogai has died and that if Tsukishima is still alive, that they'll have to make the assumptions that there are at least six fake skins in circulations. He asks Ushiyama if he had called Hijikata, and not a moment sooner, Hijikata himself comes into the room. He is carrying a cat as well as a tattooed skin in the other hand, and says that they have to find a way to discern whether the skin is real or not.
When Hijikata comes into the room, Ogata just stands silently as Sugimoto and Hijikata have a solemn conversation. When they get to the topic of Noppera-Bou, Asirpa is about to refer to him as her father when Hijikata cuts her off and threatens Sugimoto to either join forces with him or fight to the death. Despite this, Ogata was able to hear Asirpa and came to the realization that she might be Noppera-Bou's daughter. Nagakura enters the room as well and suggests that Sugimoto's group sell them the skin and go home to quiet lives, to which Sugimoto refuses, saying that they had to meet Noppera-Bou. Asirpa's stomach's constant grumbling breaks the mood and Ienaga suggests that they eat and continue the conversation over dinner.
At the table, Sugimoto comments that Ogata betrayed Tsurumi and that he might betray them as well. Ogata just remarks that he is not the type to hold grudges and that his words hurt him. When Hijikata expresses concerns over how to distinguish the fake skins from the real ones, Ienaga says that she might know someone who could help them, a counterfeit artist named Chouan Kumagishi. Later on, as some of the people head out to find Tsukishima's body, Ogata stays in the store with Hijikata to find clues. Suddenly, a Molotov cocktail is thrown in through the window, setting the store on fire. He tells Ienaga not to leave the store as she'll just be shot and killed, and while preparing his rifle, states that he saw multiple military soldiers outside.
As the 7th Division surrounds the store, Ogata heads to the second floor and began shooting at them from a window there. He is able to drive them towards the walls of the store where Hijikata was able to attack from inside, forcing them out back into Ogata's sight. However, a soldier from a distance away shoots at him, making him retreat momentarily, thus giving the soldiers enough time to rush into the store. One of the soldiers come up and enters the room but Ogata is able to surprise and stab him. It does not faze him, and he is able to knock Ogata down and starts beating him. He is saved by Sugimoto who had knocked the soldier out and he asks if he wants him to thank him as he spits out blood. Ogata returns to the windows and shoots at the 7th Division again, giving him, Sugimoto, and Hijikata enough time to flee the store. Back in the town, Hijikata tells him and Ushiyama to go with Sugimoto and Asirpa to Tsukigata as he and Ienaga joins up with Nagakura and Shiraishi.
They take an off route path through a forest in order to avoid being spotted by anyone who could alert the 7th Division of their position. When Asirpa spots some woodcocks and says that they would be delicious to eat, Ogata prepares to shoot them down but is stopped by her. The next day, he sets out in the early morning and is able to shoot three birds. When Ushiyama praises his skills, he puffs his nose in delight but his mood is brought down when Sugimoto says he must've felt annoyed by Asirpa's word that he couldn't do it. Asirpa cooks up some woodcock brains much to Ushiyama's reluctance and Sugimoto just accepting it, but he declines to eat them. They make some citatap, however Ogata doesn't listen to Asirpa's words which only led to more annoyance for him. He silently eats the ohaw as Asirpa tells them about an Ainu religious love poem.
They spent at least one night sleeping in the forest and Ogata went out to do something but came back by the time Ushiyama and Asirpa fell asleep, startling Sugimoto in the process. The next day, they continued making their way through the forest when they came across an Ainu kotan where they decide to rest at. Upon entering the kotan, they are greeted by an Ainu man who can speak Japanese well. Ushiyama points out a cage behind them, and Sugimoto sees that the bear is too big to fit in the cage. The man introduces himself as Ekurok and says that his "father" Retanno Ekasi is the leader of their village and that they should ask him for permission to stay.
Upon arriving at his house, Sugimoto warns Ogata to be on his best behavior. Another Ainu man came out and immediately went back inside, which Ushiyama noted. Sugimoto tells them that they must clean the house and they wait outside for some time and Ogata chases a butterfly in the meantime. The man comes back out and leads them inside, holding hands. As Retanno Ekasi is greeting them, Asirpa interrupts him which caught everyone by surprise. When Ekurok begins to introduce the rest of his family, they are interrupted by Asirpa again who has to use the bathroom. Once Asirpa and Ekurok's Brother left the house, Ogata asks them what Asirpa's word meant, but the two Ainu men just remained silent with a grim look on their faces as he asks if they do not know.
Even despite Ekurok's explanation and Sugimoto scolding him, Ogata continues to be wary of their hosts. They begin to argue about whether they were Ainu or not, and Sugimoto points out Ekurok's large earlobes which Ogata notes as nothing special. They are interrupted by a woman who comes to the window and yells something before being carried away by another man. At this, Ogata says that there is something strange going on. Fed up with Ogata's skepticism, Sugimoto pulls out a kisarri and have both Ushiyama and Retanno Ekasi perform with it. Upon seeing the latter with it, Ogata takes the kisarri and his Retanno Ekasi's pinky toe causing him to yell in Japanese. Despite that, Sugimoto still continues to defend them and argues with Ogata. Ogata then sees that Ekurok's Brother has returned and Sugimoto asks where Asirpa is. When Ekurok attempts to lie to them, Sugimoto sees through it and hits Ekurok's Brother with the kisarri, causing him to fall over. Upon seeing the tattoos on his legs, Ogata and the others finally realize the true nature of these men as Sugimoto lets out a menacing roar.
As Sugimoto kills Ekurok's Brother with the kisarri, Ekurok dives for his rifle but Ogata shoots him and mocks him, asking how they beg for their lives in Ainu. He then throws Sugimoto his rifle, telling him to never take his eyes off his weapon. When Sugimoto heads out to find Asirpa, he is being pursued by a convict which Ogata shoots in the head, saying that he didn't save Sugimoto because he liked him either. Unbeknownst to him, Retanno Ekasi slips out quietly behind him.
Once the fighting has ceased, Ogata steps outside to marvel in Sugimoto's handiwork when Asirpa comes out to say that Kumagishi had died. When she sees the dead convicts lying on the ground, Ogata says that it was mostly the doing of Sugimoto and notes that he is one dangerous person.
Sugimoto's Group helps the Ainu women bury the dead convicts and the Ainu women expresses their thanks to them by offering them food made with the year's harvest of turep. While they were preparing the food, Ogata points out to Monoa that the pestle she is using is the same one she used to bash the convict's head. Once the food is ready, everyone gathers and enjoys eating it together. After they had finished, they surrounded Kiyohiro Suzukawa and ponder on what to do with him. Ogata says he'll just be a pain and want to have him killed and skinned but Sugimoto decides to take him with them since they were in a hurry. They then say their farewells to the Ainu women as they leave the kotan.
They make their way back to Tsukigata and Ogata says that Suzukawa is a real letdown and that he'd be too much of a small fry to be locked up in Abashiri. However, Suzukawa retorts saying that he is a con artist who uses his head instead of brute force to get what he wants. They meet up with Nagakura who tells them that Kumagishi is dead and the group is surprised that he already knew. Nagakura also tells them that Shiraishi has been captured by the 7th Division.
Once Hijikata and Kiroranke returned from their mission and informed the rest of them that they had failed to rescue Shiraishi, everyone thought about what to do, with Ushiyama telling Ogata to check out Asahikawa since he belonged to the 7th Division. However, Ogata reminds him that the 7th Division has considered him a deserter. After some more thinking, they decide to leave Shiraishi to his fate since they already have a copy of his tattoo. However, Sugimoto refuses and says that he wants to save Shiraishi and pulls over Suzukawa, saying that they could use his skills as a con artist.
Somewhere off a coast in Karafuto, Kiroranke's group came upon some sea lions which they decided to hunt. Ogata manages to shoot one in the head but is surprised when it survived and tried to swim away. However Asirpa was able to kill it and gave some of its meat to Ogata, which he had difficulty chewing. Ogata then expresses concern that even though he shot the sea lion in the head, he wasn't able to kill it. Asirpa tells him that sea lions have thick skulls so shooting them in the head won't be as effective before sloppily eating the meat.
After finishing their hunt, Kiroranke's group is approached by a Karafuto Ainu man who offers to buy their sea lion skin as well as give them information where they can sell their meats and innards. They then come to a fox breeding facility where they are greeted by the owner as Ogata looks around the farm. Once Kiroranke had finished speaking with Asirpa, Ogata quietly speaks to him, saying that Asirpa's father Wilk, had left a key that only Asirpa knew and that since she is with them, they have the advantage over the other parties. Ogata tries to push Kiroranke to get the key from Asirpa, but he says that they should wait for Asirpa to reveal the key to them in due time.
Kiroranke's group goes to hunt some musk deers and Ogata is able to shoot and kill one. When Kiroranke carves the musk deer and takes out its musk gland, Ogata attempts to smell it only to be apalled by the odour with his mouth hanging open. Afterwards, he silently stood by as Kiroranke and Asirpa talks about her father and took on a darker look as Asirpa says that thanks to the musk deer she was able to see a part of her father that she never knew and that she regained a memory of her and her father that she had forgotten.
As they travelled through Karafuto, Ogata noticed Asirpa getting excited over a freshly laid mound of feces since she thinks a large prey must be nearby. However, Shiraishi revealed that it belongs to him as he had just relieved himself earlier.
Ogata uses a Type 30 rifle, and is a talented sniper that can easily put a bullet through a person's head under 300 meters.
He explains that the Type 30 rifles "use smaller rounds than Russian rifles, and that some say that they lack in stopping power, but for long distance shooting and accuracy, the Type 30 rifle is far superior," and that the Type 30 rifles are excellent for sniping and sharpshooting.
Ogata likes anglerfish hotpot but dislikes shiitake mushrooms.
Ogata may have been based on the American sniper, Carlos Hathcock. One of Ogata's sniping poses is very similar to that of a famous pose of Hathcock. Ogata's nickname "Wildcat" may have come from the Japanese title for the 1993 American movie Sniper (山猫は眠らない, Yamaneko ha Nemuranai), which is loosely based on Hathcock's experience in Vietnam.