He is the great-great-grandson of Shiro and Yamabuki, the great-grandson of Riki and Fuji, the grandson of Gin and Sakura, the son of Weed and Koyuki, the nephew of Joe, Kotetsu and Yukimura, the first-born brother of Bellatrix, Orion and Rigel, the cousin of Kōshirō and the second-cousin of Shion.
Sirius is a silver brindle (tora-ge) Akita Inu/Kishu Inu mix with blue eyes. His fur is portrayed bluish in color. He looks just like his father in every way.
Sirius is calm and kind, brave, strong, and smart like his father. He usually looks out for his siblings.
He is a caring, peaceful, and fair, like his father and grandfather, and looks just like them in appearance. Like his father, he opposes violence and killing, and believes in goodness. He is the wisest of his siblings, trying to solve the conflicts between them.
But he also can be stubborn and naive, as seen when he still believes he can reason with Monsoon despite the terms the bear gave him. This is because he saw a light in Monsoon at one time, and because of his young age.
He rarely loses his temper but when pushed over the limit he will attack those who make him angry.
Even though Sirius does what he believes in, he can be reckless at times and has a single minded spirit.
Though he's very persevering in achieving his goals, he still cares very much about the well-being of his friends and family, as seen when he saves his cousin Shion from drowning.
He is also very good at a persuading others like Rocket and his younger brother Rigel to take Chibi to Ohu and has big hopes for him.
Despite having grown up as a wild dog his whole life, Sirius like his family does have a soft spot for one human in particular and that's Daisuke. Sirius like his siblings does appreciate Daisuke's help when they need it showing his trust in his grandfather's owner.
Sirius makes a minor appearance in the end of the series, as he is born as the oldest son of Weed and Koyuki.
Sirius is named by Daisuke after he sees the puppy looking at the stars of the night sky.
In the beginning, Sirius along with his siblings, came down to a river to see Daisuke and Hidetoshi. They offer fish to Sirius and his siblings. Afterwards, his parents, Weed and Koyuki, called him back home. That night, Sirius decided to follow Orion, Bellatrix and Rigel out to search for river crabs.
During the volcanic eruption in Ohu, Sirius becomes frozen with fear and Orion dives in to save him. Sirius was dug out along with Orion but when eruption gets worse he finds that his brother go in the wrong and disappear into the smoke with their uncle.
Sasuke and Weed's four pups manage to survive the catastrophe and find an abandoned shed, where the puppies can be safe from the snow. While their baby-sitter scouted the area to search for any survivors, Sirius decides to go out in the storm to find his brother, Orion. However, the small silver Akita got lost and he was nearly engulfed by the storm.
The Kamakiri Brothers
Luckily, Kamakiri's sons have found him. Instead of killing Sirius, they decide to keep him as a hostage, turning him into one of their soldiers and brought him to their homeland in Hiroshima. When they arrived, they taught him how to fight and he is already a skilled fighter. When Akakamakiri ordered him to kill his opponent, Sirius immediately refuses.
As punishment, Kamakiri's eldest son grabbed him and knocked his head on a nearby tree, telling him that the law of the wild is to kill or be killed. Despite all this, Sirius is still grateful to his leader for saving his life, but still remembers about his family he had once known.
When Akakamakiri's pack arrive in Shikoku to eliminate the Kurohabaki clan (Yamabiko and Kojuro's pack) and to take their territory, Sirius is nominated to be Akakamakiri's scout and guardian.
Thanks to Sirius' bear-dog instincts, he attacks both Yamabiko and Kojuurou, managing to let his friends and his leader to escape. He eventually gets caught, but is released thanks to Yamabiko's kindness. The kai-ken puppy also tells him that his pack does not want to have a conflict with Akakamakiri's army and that they are permitted to leave.
When Sirius returns to his pack and told them about Yamabiko's message, Kamakiri's sons decide to take it as a bluff and follows Yamabiko's pack by leaving the island and that they will ambush them on the other side of the island, which they did.
While Sirius was hunting the next day, he stumbles across the Ouu army and Sasuke quickly stops him. Although Sasuke insists that he joins the Ouu army, Sirius refuses, telling him that he belongs to Akakamakiri's pack and that their goal was to kill the Kurohabaki clan and runs away.
Later, when some of his friends were being pursued by Orion and the Ouu soldiers for spying on the Kurohabaki clan, Sirius stops his younger brother and recognizes him. He explains to Orion that Akakamakiri saved his life months ago and is truly in dept to them and no matter how many times both Orion and Tesshin tried to put some sense into him, Sirius considers the Ohu army and even his brother as enemies because they have joined forces with Yamabiko's pack.
As Sirius runs away, he cries in regret for betraying both his younger brother and his family's pack. When he returned to his pack once more, Kamakiri's sons made the decision that they will attack the Kurohabaki clan at dawn.
Worried about his brother and his pack, Sirius tells this to Toshimitsu, one of the Kogas, who eventually told Sirius' message to Orion and Yamabiko's pack. He is almost ready to turn Ou side, but then ends up defending the Akakamakiri, Ou army, and remains in Akakamakiri's pack. Later, when Kamajirō dies, Sirius cries over his death and with that he, Kurokamakiri, and the others join Orion's forces, while Akakamakiri leaves outcasted from his pack.
The Ōu Army
Orion's pack return to Ohu and combines with the troops. Sirius quickly goes with Orion to see his parents, who are in the care of humans. Weed's leg has improved. When the Ohu army is preparing to fight Masamune and his army, Weed and Sirius are present among the group. Sirius is involved in the fight against Matheus.
During the battle against Masamune he sees Orion trying to kill Kurohabaki Clan leader but Orion is stopped their father Weed with Sirius and Bon looking in shock. Just like the other soldiers, Sirius couldn't move because even if they wanted to support Orion they didn't have courage to move. When Bon and Sirius saw Orion give into his anger and attack his father. The two quickly try to stop him but Weed tells them not to move and with shock he watches Weed banish Orion from Ohu. He sees Orion starting to leave in tears and angry but him and Sirius tell Orion to wait.
As Sirius and Bon try to catch up to Orion; Izou speeds past them, he hears Izou say that Sirius is Ohu's successor but Orion will need someone to look after him
At the end of the battle, Masamune ends up committing suicide. Sirius covers Masamune's body with a scarf. He shows compassion for the grieving Yamabiko, because even though Masamune was evil, he was nevertheless Yamabiko's brother. After this, Sirius and the other puppies follow some ravens and find Kojūrō's body. They bury it together and thanks to Irish hound brothers mother guiding Bella back he quickly reunited with her.
Later, Ohu's last spring, the first in which Sirius has experienced, arrives.
Sirius has been training with his brothers at the Akame Mountains for 6 months. Sasuke arrives at the base of the mountain to be greeted by Sirius and Rigel, who take him to see Orion.
Upon hearing about the crisis in Ou from Akame, who has traveled several miles whilst injured to deliver the news, Sirius and his brothers head off to find recruits and help their friends. On the way, Sirius encounters Unsai, a former Ou soldier and close friend of the Ou army. Unsai sends his subordinate, Kawasemi, with him and Rigel.
Eventually the come across the same gorge leaped across by their father and grandfather. The two brothers easily jump the gorge and help Kawasemi when he slips, carrying on their journey.
Sirius meets up with Unsai, Shion and the others and witnesses the death of Kenshin who was attacked by Monsoon. As the dogs try to leave, Monsoon sees Sirius and remembers a time when John killed his siblings, but was attacked by a young Gin in return. Sirius is allowed to carry the bodies of Kenshin's comrades away, much to even Monsoon's confusion.
Sometime later, a flood causes a wounded Ken to be washed into a river and the Ou army go to the location to find and save him. They each keep a watchful eye on the raging river, as Kawasemi dives in to find him.
Ken is rescued safely and Sirius continues with Orion. Sirius becomes more and more agreeable to the point of letting the bears live, despite his brothers opinion. Shion agrees to talk to the bears to come to some kind of agreement, with Unsai and Bob following. Sirius follows them too but unknowingly runs onto Monsoon's back, who was lying down in the trees out of sight. Upon seeing the bear, who in turn sees him, Sirius freezes in his tracks as Monsoon angrily roars and begins to thrash around violently, knocking down trees to reveal Akame and Tesshin in the grass nearby.
During the battle, Sirius sees Izo trying to fight and with his brother he grabs Izō and gets him to safety while Orion distracts Monsoon.
Sirius tell Izo and other dogs that Monsoon is angry because he doesn't understand dogs. He said 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. Izo tell him that how long he gotta be naive and can't live in the wild if he kept thinking. He knock him off on ground and tells Sirius don't speak like a fool.
Akame ask Sirius if he's still hesitating and tell him that he's in the way and then get out. Sirius reacted around Monsoon. He started circling in the enclosing area. He jumped on Monsoon's body to get sickle and. Akame tell Sirius it's his turn and think about he's going to cut him. Akame ask Sirius that he're tried to bring down paradise. He soared above his allies's heads with his back at Monsoon. He tells everyone that they're all making a mistake and ask them that how much blood are they going to spill until they are satisfied. He said this is why they're fighting each other.
Sirius turned his back on Monsoon. Orion tell Sirius that it is his fault. Unsai tell Sirius to help Orion. Unsai tell him that he can't let Orion die, Sirius threw the sickle away and ask him what are he thinking.
Sirius tell Shion to listen to him, he says okay. Orion ask Sirius why he toss sickle, they need it. He tell him that he's exposed if he don't want to fight and get out of way. Sirius tell him be quiet and give him five minutes. He tell Monsoon that he hear from Bob that he came to revenge on dogs and tell Shion interpret his words. Shion tell him about Monsoon ask Sirius if he have authority of a leader. He say it'll be okay whenever everyone will abide by Monsoon depends on his terms. Shion tell Sirius what Monsoon say and if Sirius remember about Monsoon's conditions and dogs are his food.
Sirius tell Monsoon to come out and ask him that he are not done talking to him. Orion tell him to leave and explan that when Monsoon comes out of the woods, he gonna use that technique to settle it. He ask Orion if he talking about the Battouga and it's impossible that can't possibly have any effect on Monsoon. Orion charge at Monsoon and tell everyone this is where it ends and if his move doesn't work, then he'll just die trying.
Sirius watches his brother's attack fail and told by Yamabiko to take his brother and run but refused when he still believed he could reason with Monsoon. While trying to talk with the bear, Monsoon was getting his claws ready to attack Sirius with everyone looking in horror.
Just as Sirius was about to get struck by Monsoon's claws the bears heard a booming sound which turned out to be Daisuke and his mentor firing at the bears.
After the bears flee Sirius wanted to take the time to come up with a new plan but Orion was still mad at him for not coming to grips with reality and throwing away the sickle. He said to Orion that he was trying to think about their future. It wasn't only his brother that wanted Sirius to come into terms with reality so did Tesshin's last subordinate right up to the point of asking if he was going to side with the enemy. Then, he saw Daisuke and went to greet him with his brother Rigel. Then, he and Rigel sees everyone in a panic because Unsai collapsed from his own injures.
After seeing that Unsai is in the care of his grandfather's owner, Sirius tells Rigel and Shion to follow him as well as asking Bob for his cooperation.
As they go off to find Monsoon, Bob tells Siruis he can't talk to him while he's rattled up. When they approached the forest they heard someone coming but it was only Akame's group and he still doesn't agree with Orion's way of dealing with Monsoon. Sirius was reminded by Orion that not only were their friends getting killed and hurt including Unsai, their dad and grandpa but also eaten. Sirius tried to tell Orion that it's hard for him too but the red akita didn't believe him hearing Orion say words that would put on the path of separation.
Then, he began to ask his comrades who made Monsoon into a brute, Akame couldn't forgive Sirius anymore and tells him that he has insulted the old soldiers who have died defending their paradise. But, Sirius says he wasn't insulting anyone, he understood that the quarrel with Monsoon goes back his father and the interaction with humans taking away his home.
Next, he was asked by Orion what are you going to do become food for the bears he's trying to protect having enough of his brother criticizing him. Giving into his anger at last Sirius and Orion charged at each other until the fight way broken up by Andy.
Even though, the fight between Sirius and his brother Orion was broken up by Andy the opposing views still placed a gap between them. Then, he saw Akame collapsed from exhaustion and the kishu told Orion to take the sickle. When Sirius tries to take it he gets pinned by Rigel thinking he's going to run away with it again. With that Orion calls it the last straw, to everyone's shock including his own Orion disowns him as his brother.
Continuing the argument with his brother, Orion asks him which is more important the lives of their friends or Monsoon's. Seeing the red akita mix's anger he gives Orion permission to attack him but then Rigel comes in to protect him. Orion asks him again how could he think that we could live with them but he is told by Akame that he couldn't think of Orion as the enemy.
Orion still couldn't believe that him and Sirius couldn't see eye to eye, given with no choice left Orion throws the sickle giving Sirius a slight head injury. The akita mix tells his brother that he does understand his thoughts but if Orion attacks in the name of revenge there will be retaliation and that if doesn't let it go it will imprison for the rest of his life. Sirius also says if Orion lets go of his revenge then they can get along, but the pet squad and the hunters arrive knowing that the bears will get killed he tells them to run. He asks Shion to translate what he's saying but Shion said those bears are evil and Akame said he can't have sympathy for them. The silver akita runs to Futago Pass wishing to talk.
Sirius continues to run towards Monsoon's bears, he rushed up to the top of Futago Pass wishing to talk to them. Seeing the number of bears everyone thought that Sirius was being foolish and couldn't help him with his strange behavior. He ask Shion and Bob to come up and help translate what he was saying, but even Shion knew it was too late to reason with them.
When Sirius saw that Zion wasn't coming he began to question if it was Orion's doing. If it was then, he said that Orion wasn't was capable of being a leader with great tears in his eyes. Sirius turns away from his friends seriously still believing in his ideals even if he had to do it alone. Just as Sirius was about talk the bears were about strike him until Hidetoshi, the hunters, Daisuke and the Pet Squad arrived. However, the silver akita refused to move until Daisuke commanded him.
After the ordeal was over, the Pet Squad felt great pride in defeating the bears excepted for Sirius who didn't reflect about his own actions.
When all of Monsoon's Kin are killed, Sirius and his brothers are greeted by Daisuke and he hears his comrades howling for victory but it's cut short by Orion. Then, he tells Orion to quit getting everyone rattled up and the silver akita mix says this useless battle is over. Shocked at what Sirius said Orion says that they've haven't lost yet and no dog in this army takes losing for an answer and he even asks Sirius when did he become so gutless shocked at Orion's words.
Andy tries to break up the fight, then Orion begins to suspect that Andy is siding with Sirius too until Akame stopped the fighting. Shocked to see Akame stand up, Akame asked what should they do now, Sirius begins to answer but is stopped by the kishu wanting to test his brother's judgement. After Akame gets a satisfied answer from Orion he turns his attention to Sirius saying that he is too tender hearted and he'd be the first to lose his life in battle something the kishu wanted him to understand.
If he wants to pursue his ideals, then Akame was alright with that and it's not a bad thing to do. But, before Akame could finish telling Sirius what to do he collapses.
Sirius still chewed out by Orion because he refuses to fight the bears, then Akame grabs his attention the akita mix tries to apologize for his mistakes but Orion has had enough of his excuses. Sirius was known for his kindness and good heart using it to move others but that kindness would get him killed, then as a last request Akame whispered something into his ear assuring he would care out the request.
Then, watches with horror as Akame collapses, but thanks to Daisuke and Hidetoshi; he is revived but needs treatment. As the rest of the dogs watch Akame and Izou leave, Sirius leaves with shion to fill out the kishu's request without saying goodbye.
Sirius still wants to talk to Monsoon, Zion and Sirius are stopped by Bob tells them that Monsoon isn't someone they can reason with. Using himself as an example convincing them not to go and why would a bear lend it's ears to a dog, the akita mixes just say Bob is speaking with energy now that Monsoon isn't here and would do the opposite if he were here. But he still considers them blind to the truth and Sirius considers that's the reason why Bob won't trust them. Shion listens to Sirius tell Bob that Monsoon has given up on him and that he's free to live the rest of his life in paradise as long as he doesn't cause any trouble. With that said they quickly leave but are stopped by Gennai who wants to come with them but Sirius says they were going compromise with him not to fight and quickly run past him following Monsoon's scent.
Sirius is seen with Shion entering Monsoon's territory looking for him. They find Monsoon at the top of the waterfall but when they try to talk to him. Monsoon still looks angry and throws a rock at them but he refuses to give up.
The two continued the search for Monsoon all the way into nightfall and they find a cave behind the waterfall for them to hide in. But upon being in the cave Sirius and Shion discover that Bob uses the cave to escape the torture of Monsoon when Shion asks why Sirius is doing this all the akita can say is that everyone Monsoon cared about was killed right before his eyes understanding the bear's grudge against dogs. But he also doesn't want Monsoon to hurt others and Shion says we're only food to him; Sirius says that the only reason Monsoon sees them as food is because of his grudge.
When morning comes, Sirius and Shion sense Monsoon's presence on the other side of the cave but Sirius tells Shion not to go out there as they see his claws come through the cave.
They try to move further back into the cave but it's no use, Monsoon finds them but Sirius and Shion escape under the water but seeing that his cousin can't swim he brings Zion to shore. Seeing that Monsoon is having another one of his tantrums the two flee by climbing the waterfall but he still refuses to give up.
As Sirius and Shion continue their persute Monsoon lashes out at the pair again destroying the forest in the process refusing to listen to the dogs Shion tries to talk Monsoon out of revenge but it was no use because he tells them that his only goal was to eat all the dogs. He gives them another condition if they give up their friends as food, then he won't kill the dogs at random; but says he'll never negotiate with them and leaves.
After that Shion starts to see the hopelessness of the situation saying to his cousin that Monsoon isn't the kind of enemy they can talk to and that they should go back. Sirius corrects him saying that Monsoon just talked to them now and wishes to continue.
The two have been tracking Monsoon for days but have a hard finding his scent since it was so strong. Then, Sirius is asked Shion why does he want to get along with Monsoon and reminds him if they fight Monsoon directly both sides will be in danger but even if they could stop the fighting Monsoon couldn't be trusted.
Then, they see a group of hunting dogs, Shion notices that the dogs belong forest watchmen but understanding the danger they're in the two leave to warn them.
Shion and Sirius make it to the hunting dogs and humans to warn them about Monsoon but they are approached by the dog's owner. But as soon as the dogs got Monsoon's they dashed after him with Shion and his cousin telling they don't stand a chance but they don't listen. Sirius pushes Shion to keep up and says that he is doing his best but tells Sirius to go on head.
Seeing what Monsoon had done he hears Shion tells him that the humans will take revenge against him and that he'll die in his home. Before the lasthunting dog is killed Shion manages to distract him and Sirius gets him to safety. Shion points out to his cousin what happened and he hears Sirius saying they are on the first step of breakthrough.
Sirius and the others hide while Monsoon continues to look for them but then they hear Gennai and his group close by.
Sirius triesto stop Gennai but all he says is that we're nothing but food to him with Monsoon's claws coming down Gennai pushes Sirius out of the way. Sirius begins to cry tears of regret after that Monsoon puts his paw on top of Sirius knocking him out and when he comes too he gets a hug from Akakama. Then, Sirius and the others notice a helicopter and begin to assume that the humans have spotted Monsoon. With his friend alright he tells them to take Akakama back to Ohu. Still persevering as ever, Sirius wanted to talk with Monsoon and the others still call him a fool for doing so but he assures everyone that he'll be alright. They believe that Monsoon is a monster, but Sirius calls them wrong, desperately wanting his ideals of peace to come true.
Then, he reminds them again that he to talk to Monsoon not fight and Andy says it's okay to risk his life but not Shion's. Just as he was about to run off to find Monsoon he stopped Andy and says that everyone risked their life for him. Sirius was thankful for it but he begged for them all to give him a chance. Gennai as mad as ever tried to have Sirius wake up to reality but the akita took a hit from Gennai.
After that they heard a cry for help and find Paulie still more convinced than ever after seeing this Sirius thanked Gennai for his words and left with Shion. He begins to see the helicopter return and hides in the bushes understanding that Monsoon won't come out with humans around. Sirius and Zion notice Gennai's group leading the helicopter to Monsoon suspecting that they are following them and shocked they won't listen.
They continue to watch Gennai's group from afar until they leave. By night fall, they hear a scream to discover that it's Monsoon who killed his own kind a mother bear and now was prepared to kill the cub. Astonished, that Monsoon would do such a thing because the cub wasn't of his bloodline. He asks Shion to convince Monsoon to let the cub go and yet he still doesn't believe that Monsoon is a monster. Then, Sirius leaps on the bear's back trying to get Monsoon to let the cub go. But he gets thrown off but doesn't get flatten by the bear. Sirius sees Rigel and the Kamakiri brothers coming and attacks Rigel out of angry and Monsoon starts to get angry himself.
Sirius tells the three of them to go. Despite Shion's best to calm Monsoon the bear flew into a rage but they escape with the cub into tow. He sees that Rigel and the Kamakiri brothers still here but before they go Sirius gets asked by Rigel why is he doing all this and all Sirius says is that Monsoon was in such a quick hurry for revenge which was his first mistake. He did understand that the dead couldn't be brought back and yet he couldn't let the living suffer anymore either and didn't want anyone to be unhappy, before Akakama and the others leaves he warns Sirius that lives will always be lost in times of war and if he dies then Akakama will be right behind him. When morning comes Sirius is asked by Shion what are they going to do with the cub and says that the cub will stay with them until he comes independent. Sometime later, he and Shion help the bear cub make a grave for his mother the cub was so heartbroken that he cried until he fell asleep. Once the cub awoke, he hears that Zion had the idea of teaching him dog language in doing so they give him the name Chibi.
Seeing that Chibi wasn't safe, Sirius and Shion take him to Rigel and the others. He tells them that he hasn't given up on Monsoon he asks Rigel to take Chibi back to Ōu with him and Rocket, then he believes that Chibi is the key to stopping all wars between the dogs and bears. After Rigel agrees, he stays in Monsoon's territory with Shion and wishes the cub well.
Continuing his search for Monsoon Sirius tells Shion that he doesn't like to be formal and will not his cousin's playing around. They smell the bear's scent all over but has a hard time finding him soon the pups notice a rock slide heading straight for them Sirius and Shion get out the way and suspect it was Monsoon's doing. He gets warned by Shion to get out of the way if he doesn't want to die but all Sirius does is stand there begging the bear to wait and shocked that he won't talk to him. A rock heads straight for Sirius and yet he still doesn't until Shion pulls out of the way calling him an idiot.
Then, he gets a stern scolding from his cousin for being reckless but Sirius becomes oblivious to what he was saying and tells Shion to lend his voice to Monsoon. He says to him not to worry about the timing and just do it commenting that the bear is curious about them, he hears Shion say to Monsoon what he was doing was dangerous and he and Shion are the only ones willing to stand up for him. When Monsoon walks away Sirius still believes it will take some time to persuade him but when Shion tells him to give up he refuses saying that Monsoon was able to control himself and in time we'll have a proper discussion. He hears the voices of the Kamakiri brothers and becomes angry that they disobeyed him for a second time, finds they over the next ledge. Sirius says that the brothers are being selfish again and warned them not to get Monsoon excited upon meeting them he gets told by Kurokama of Gennai's battle plan and Akakama tells him he get his turn but let the pyrenees take this chance for him. But Sirius is surprised over what Gennai is trying to do.
He begs Gennai not to provoke Monsoon but he is held back by Akakama who informs Sirius that he has their support in making peace with the bear and that all past grudges will be let go if Monsoon doesn't mess with them. Sirius also gets informed if he saves Monsoon from Gennai the relationship will grow once the bear is on his back he hears the pyrenees call out to attack him to which he does. Playing along he hears Gennai say that he and Shion have double-crossed them but Sirius is told by Gennai that he and Zion should run but he tells Gennai to run instead. Getting the idea Sirius and Shion get chased by Gennai until Monsoon intercepts them.
Surprised by Monsoon's actions Sirius sees him attack Gennai and the Kamakiri brothers after Monsoon short leaves he and Shion check on Gennai relieved that he's alright. Meeting up with Monsoon, Sirius is picked up by the bear and stops the Kamakiri brothers and their friends from following them saying if they provoke Monsoon all of his work would be for nothing. Sirius is walking in the mountains with Shion and Monsoon.
Sirius is swimming in a lake with Shion and Monsoon when the bear pulls his cousin under the water Sirius speaks in bear language for the first time. Seeing what the bear was trying he commands Monsoon to put his cousin down saying that despite joking he was scary. The sudden appearance of humans causes Monsoon to flee and become separated and he waits for Shion.
Sirius still continues to go after Monsoon wanting to build his trust and reminded Shion that a lack of it was the problem accepting that he was prepared for the worst forgiving Monsoon if he is attacked. Finding Monsoon Sirius was surprised to see him waiting for them translating he hears that Monsoon is using abusive language again. When asked by the bear if he brought the humans with them he says they're not coming then he has his head pushed into the ground by the bear's claws assuring Shion that Monsoon was just playing. Surprised Monsoon with his own playing and when he saw the Kamakiri brothers coming he becomes angry and throws them down saying they broke their promise.
Seeing that Monsoon was wary of the Ohu Army Sirius assured him they weren't but when Monsoon didn't care if they did. Sirius was surprised about that because was trying to stop this fighting, afterwards he and Shion reunite with Chibi seeing that he has grown and take him from the village meeting with Orion, Rigel and their friends along the way.
He tells them that everything is peaceful for now and that everyone is amazed that Sirius came to agreement with Monsoon all but Orion. Soon the brothers get into a heated argument again but it was stopped by Sasuke who had announced that everyone had return.
Sometime later, during the winter, the Ou army decide to finally start their attack on Monsoon. Orion, having learned valuable ninja techniques, uses his sickle to fight much to Sirius's dismay. Before the final fight can begin, Monsoon lashes out in anger at Andy, having had flashbacks about his uncle, John. Andy dodges out of the way and Sirius is caught by Monsoons claws, sending him flying several meters through the air. Despite his injuries, Sirius forgives Monsoon and tries to calm everyone down, only to end up fighting with Orion again. With Sirius badly injured, Monsoon tries to flee with him and is cornered at the sea with Orion close behind. Monsoon leaves Sirius on the shore while he tries to flee into the water but is followed and killed by Orion. After seeing Monsoon die, Sirius dies from his own injuries.
- On the constellation of Orion the Hunter, the stars Bellatrix and Rigel are present while Sirius is not. That makes him the only of Weed's pups not to have his name in the constellation.
- He is the third dog to speak bear language, following Bob and Shion.
- He is the first and only one of Weed's children to die.