Yūma Chiaki, or Thor, as he is more commonly known, was formerly the Seventh Fist of Ragnarök and currently a captain for the Shinpaku Alliance.


Thor is a very tall and large-framed man. He is lightly-tanned with short black hair and with long sideburns. He sports a defined and well-muscled build with a large belly; what he considers the perfect mixture of muscle and fat. He typically is seen wearing a sleeveless kimono to show off his muscular arms and usually doesn't wear any footwear, but sometimes wears sandals as an option. During his days as the Seventh Fist of Ragnarök, he wore black gloves with golden marks insignias shaped like Roman numeral for "7". Recently, Shigure has given him Steel Arm Guards, along with the rest of the Shinpaku Alliance.


He fights using a combat-sumo fighting style and joined Ragnarök in order to make his dream of making the combat-sumo style mainstream. Despite being in Ragnarök, Thor has a high degree of honour, capable of reasoning with foes, and considers upholding the rules of sumo wrestling his top priority. Thor is also perceptive, even while in an imminent rage, having immediately discerned exactly who Kenichi was after their first encounter based on the information that Siegfried passed on to him. Thor believes that the Shinpaku Alliance is composed of true comrades, unlike Ragnarök, during which he believed Siegfried was the only person who was his comrade.

Thor has a strong liking for fellow Sumo Wrestlers. Such as in the D of D Tournament, he cheered for one. He also says things that most Sumo Wrestlers say.

Thor is also afraid of heights, such as when he needed to jump out of a helicopter, he grabbed the side stating he couldn't do it. However, he put his fear behind him for the sake of his friends. Like Kenichi, he is also afraid of riding dangerous rides such as roller-coasters, something Kenichi shares with him.


Thor practices a hybrid martial art heavily based on traditional sumo. An interesting note about Thor is that he was never trained by any master in combat-sumo, yet he achieved his level by pure hard work and training. Ikki Takeda even said that Thor, who achieved his level without a master is " simply beyond belief", demonstrating that underneath his supposed stupidity, he shows ability through his determination and hard work as a martial artist. Thor would later receive some training from Danki Kugatachi, greatly boosting his already formidable fighting skills. During this time, Thor was able to learn various things from the staff master, including fighting against weapons barehanded and learning how to dodge weapons. The fact that Thor was able to learn and create new skills for his combat-sumo style from Danki, despite the fact that the latter is a weapons master, and the fact that sumo and staff techniques have nothing in common with each other, shows how determined and dedicated Thor really is about achieving his dream of perfecting Sumo.

  • Hybrid Sumo Wrestler: Thor has taken traditional sumo wrestling and combined it with street fighting tactics and techniques in order to create a more battle ready variation which he calls "Combat-Sumo", as a result his fighting style is considered to be a form of hybrid martial arts. As a hybrid martial artist, Thor's fighting style, training, and movements do not revolve around any single discipline, minus the ways of sumo wrestling. Instead, Thor takes whatever type of fighting tactic he can get; punching, kicking, palm strikes, throwing, take downs, etc. and incorporates it into his combat-sumo in order to effectively fight more varied opponents. In order to make combat-sumo more effective in battle, Thor is constantly finding new ways to make his style more adaptable, the greatest example of this adaptability is when he took what he learned from Danki Kugatachi, who is a staff master, and later became able to fight against weapons just as well as the other members of the Shinpaku Alliance, which shows how versatile his Combat-Sumo style has become.
  • Immense Tenacity: It should be noted that Thor's greatest skill is his determination and hard-working attitude. With this determination alone, Thor has constantly conditioned his body and developed his sumo style far beyond the normal level of regular sumo. With this determination he trains every single day in ways that seem very unreasonable to a lot of different fighters, and as a result, Thor has become a type of fighter that can handle fighting a variety of different fighters and styles despite using a style of martial arts that originally would not have been effective against large variations of martial artists. The fact that Thor was able to achieve this level of fighting by himself without a master leaves a lot of fighters speechless, and after receiving the teachings of Danki Kugatachi, Thor became motivated to work even harder, and is now capable of fighting weapon users.
  • Enhanced Endurance: Thor trained his body to accumulate a combined mass of muscle and fat that renders him extremely resistant against normal attacks. Even against powerful attacks from YOMI fighters such as Rimi or Lugh, Thor is able to shake it off like it barely hurt him and continue fighting. His durability is thanks to the Valkyries having trained with him constantly by striking his stomach and hardening his muscles with their weapons. During his training against weapons, his master Danki told him to attack while trying to make his body as small as possible, which has greatly helped increase his overall defence.
  • Enhanced Speed: The training that Thor underwent after Ragnarök disbanded dramatically increased his overall speed. So much that even Freya (who is a swift fighter herself) commented on this attribute. During his training with Danki, he learned how to carry his body when moving, which has given him the ability to quickly dodge and fight against weapons despite his size.
  • Enhanced Strength: Befitting his large build, Thor has a great amount of strength, such as being able to push a large bolder more than twice his size with little effort and lift it, as well as several others with considerable strength. He's able to send multiple enemies flying with his attacks.


Thor's past before joining Ragnarök is unknown. What is known is that Thor's goal for making sumo a mainstream fighting style lead to him getting into multiple street fights as a way to develop his unique fighting style. Thor's motivation for joining Ragnarök was also to pave the way for his sumo-based dreams, climbing the ranks of the organization to the point where he became the last member of the strongest group of fighters in Ragnarök, the Seven Fists (later renamed the Eight Fists after allowing Kisara Nanjō to become the Eighth fist). Using his influence as the Seventh Fist, Thor began running his own fighting ring in the streets, naming it the Sumo Stable, as a means of not only maintaining the followers he has in Ragnarök, but also to give himself a continuing supply of opponents to develop his fighting style. During his time in Ragnarök he also began to develop a bond with the Fifth Fist, Siegfried, becoming close friends with each other despite the overall lack of friendship and closeness with the other members of the eight fists.

Ragnarök SagaEdit

Betrayal ArcEdit


Thor vs Kenichi

Thor runs a fighting ring, where the Shinpaku Alliance sneaks into and suddenly attacks the members of the ring, and claims (ironically correctly) that in this situation, Ragnarök was the one being attacked. He figures out who Kenichi was among the invading Shinpaku based off of Siegfried's information and the two step into the ring. Before the duel, both state their conditions if victorious: Kenichi's is to have Thor quit Ragnarök, while Thor's is to have Kenichi train under him in combat-sumo. Thor possesses an imminent advantage against Kenichi in his large amount of strength and endurance, neither of which allow Kenichi to harm him sufficiently, though is impressed by Kenichi's endurance. He soon comes under attack from Kenichi's Strongest Combo and receives hits to the head from the Kao Loi, further impressing him. Thor loses when he is thrown out of the ring by Kenichi and honours their agreement, though gets a severe beating from the remaining members of the Eight Fists as a result.

Final Clash arcEdit

He later joins the Shinpaku Alliance as a favour to Siegfried. However, since he promised to quit "fighting", he defeats Loki's subordinates under the pretence of "practising" his techniques. When Odin tries to attack Niijima, Thor steps in and tries to hold him off and is easily defeated and left severely injured. Just as Odin is about to kill him, Kenichi arrives at the last second and saves him. After healing his injuries, he assists in fighting Ryūto's grunts and cheers for Kenichi to win.

Yami/YOMI SagaEdit

Spark ArcEdit

Some time after Ragnarök disbanded, It was mentioned to Niijima that Thor's territory, "The Sumo Stable", was attacked by a mysterious member of an organisation called Yomi, when Thor himself was not there to defend it, leading Thor to recognize Yomi as a threat.

DofD Tournament ArcEdit

Thor is confronted by Niijima during one of his training sessions with news about an upcoming tournament involving Yami/Yomi.Thor participates in the D of D tournament as part of Shinpaku, and is among the rest of its members touched by Mizunuma's bravery and sacrifice, quickly rushing in with Kisara, Freya, and Takeda and knocking out three of the opposing Black Squad members with Thor's Hammer. He is nearly beheaded when he rushes at Captain K and is narrowly saved by Freya, who notices the steel wire, upon which he leaves the weapon battle to Freya. After the match, he is seen cheering for the Mongolian Bufu Team for being composed of sumo wrestlers like himself, but becomes horrified at the ferocity with which one of its team members displays in fighting the opposing Karate team member, not to mention that the Bufu team member was smiling and waving at him while speckled with blood after the onslaught. He becomes tense during the night, practising his sumo techniques ardently and arguing with Takeda to keep away from him while he does so. He is gravely injured by Sho Kano when he attempted to save Miu, confining him to the sick bed and rendering him unable to fight in the later matches. During the invasion of Despair Island, he teams up with the other injured Shinpaku members and Hermit and defeats Fortuna.

Weapon Fighters ArcEdit

Some time after the DofD, Thor told Siegfried that he started having doubts about the limits of his sumo style. Siegfried suggested talking to Freya about it, and in turn she asks her grandfather, Danki Kugatachi for help. During this time he was able to improve his skills and faith in sumo and also learn how to fight against weapons barehanded. In rescuing his master Danki, he along with the other Shinpaku members fight a weapons Yami group and fight them. After Danki and Kenichi is saved, Thor goes home with his master and trains with The Valkyries.

Okinawa ArcEdit

After hearing from Niijima about a Yami base in Okinawa, Thor accompanies the other alliance members to Okinawa to help the masters fight them despite them saying otherwise. At the night, Thor stays down in the lobby of the hotel to make sure the masters don't go by them so they can follow them. However, they all (with Miu, Kenichi and Niijima by accident) all leave them and Thor talks with Siegfried believing this to have been a peaceful night.

Yami Transport Data ArcEdit

When Niijima gains data on Yami and the members need assistance in fighting their opponents, Thor was arriving with Freya and Siegfried out of a plane, however, Thor couldn't jump due to his fear of heights, but jumps for the sake of his friends. Unfortunately, he lands off course and eventually ends up in the cross-hairs with Miu's fight with Rimi over the disc on Yami. He helps get the disc back and does his best to keep it from falling into Rimi's hands only for him to accidentally breaking it from his grip. Afterwards, Thor and Miu are sad that it broke and later relieved that Niijima actually had the real one all along, causing both Miu and Thor to get angry over Niijima for such a trick. He helps fight Ishida (who was a Yami member inside the Congress) and after he's defeated by Sakaki, they all go home having completed their objective.

The Tidat Kingdom ArcEdit

After hearing from the others about Miu being kidnapped by Jenazad, Thor offers his assistance in any way he can and wishes Kenichi the best of luck. He later is present when Rachel offers her assistance and helps locate Miu's last location and let Kenichi know about it.

Titan ArcEdit

Following the discovery of a Yami base, Thor and the rest of the alliance head out to the base while holding onto Niijima having forced the information out of him. However, the masters force them to stay as they fight. They are met by the limo that picked up the YOMI members from before and Thor is shocked to see Berserker and a new member named Lugh. As Niijima confirms Berserker joined Yami as Ogata's disciple, Lugh decides to fight the alliance and is shocked to hear from Siegfried that Lugh is blind. When Lugh seemingly kills Siegfried, an enraged Thor charges at him only to have his arm broken but is saved at the last second by Siegfried who snapped his neck back into place. Thor then manages to snap his arm back into place revealing it was only dislocated. He later watches as Takeda challenges Lugh alone. As Takeda attempts to sacrifice his left arm, Kenichi interferes not wanting either to damage themselves this far. Lugh decides to leave, but not before promising Takeda he'll come for him first next time.

He later attends the amusement park with the rest of the Alliance. He marvels that the rides are able to let people ride in their swimsuits and notices that Kenichi has been avoiding them for a while and when some Valkyries ask him to come only for Thor to state his shoulder isn't healed and Kenichi also notices it and the two bump fists with each other noting their fear of scary rides. They both then eat and marvel at how people want to ride dangerous rides and promises not to tell Miu his fear about them. He then shows his surprise at Miu's travels with her grandfather and how she gave up so much for the sake of martial arts. As Kenichi decides to ride the merry-go-round with her, Thor comments to himself how Kenichi's heart has become so much stronger. He then talks with Siegfried and believes he saw Tanaka from the DofD Tournament in the crowd, but Siegfried doesn't see him, much to Thor's confusion.

At night, he runs into Niijima, some Valkyries and Matsui and notices nobody is here and sees a fire which causes Niijima to ask Thor for protection. When he discovers everybody is fighting YOMI but him, his left arm is hurt from Niijima grabbing it and realizes it's because he's injured. He then is rallied by Niijima as he says they need to regroup and prepare for battle. They make there way to Renka's and Rachel's fight and are shocked (and pleased) seeing the two half-naked from fighting, much to there embarrassment and causes Renka to kick him in the face and causes Rachel to leave ashamed of using non-flashy moves.

He along with the rest of the alliance leave after having gathered everyone else as Thor carries an unconscious Takeda out of the park.

The Eternal Sunset ArcEdit

Days later, Niijima greets most of the alliance after the battles and points out how Rachel and Chikage haven't gone to school lately and Tanimoto is going to school like nothing happened. When asked about Kenichi and Miu's whereabouts, Niijima states that they went to see the people who got out of the darkness: Ryūto and Rimi. Several days later, Thor shows up with the rest of the captains, gather at the base waiting for Kenichi and Miu. Kenichi and Miu notice that Apachai and Shigure have been waiting at the base asleep the whole time, waiting for everyone to show up. Shigure then wakes up and tells them that she has something to give them, and then takes the bag away from a sleeping Apachai and hands all of the captains the arm protectors that she made for them, with Thor noting how the protectors doesn't ruin his harite, much to his enjoyment. Shigure then demonstrates how strong the gear is against a weapon, which amazes everyone.

Later, Kenichi and Miu inform him and the others of Shigure's capture, shocking everyone. Once the alliance learns of her location, all the alliance members set out with Okamoto to find her. Thor was then present as he expresses his desire to help everyone fight against Yami. Just then Okamoto enters to tell them of there arrival and the Shinpaku Alliance readies for battle. After Okamoto takes out the soldiers at the bay, Thor and the others dock on land and enter the forest. Once they are ambushed by Yami soldiers to which Thor and the others are able to easily fend off, much to the soldiers surprise. After seeing Kenichi defeat one of them with Sōtenshū, the enemy soldier is knocked unconscious and Thor adds that impact attacks are still effective against the enemy's armour. After Okamoto agrees to hold them off on his own with his men, Thor and the others escape. After reaching a waterfall, Thor and the others are confronted by the YOMI disciples.

After seeing them launch towards them, Niijima tells Miu and Kenichi for them to take advantage of the situation and run. Though hesitant, the trio leave after Thor and the others encourage them to move ahead. After they leave, Thor and the others lunge towards the Satsujinken disciples

As the battle progresses, Chikage runs towards Ukita's direction and he prepares to fight but she simply runs past him and heads towards Thor's direction. She kicks Thor behind his knee causing him to lose balance and giving the female kodachi disciple an opening to stab Thor in the thigh. Hyōgo then proceeds to stab Thor on the shoulder and Siegfried comes to his aid but ends up being slash by Hyōgo's fellow kodachi disciple. As they continue to be overwhelmed by the armed division, Chikage suddenly defends them on the grounds that the armed division has no honour ganging up on them. Chikage replies that they will be supporting the Shinpaku Alliance, albeit temporarily, in order to protect their masters' pride.

Once they start to overwhelm the weapons team Hyōgo starts to have them work together more effectively. Just then, two masters: Sōgaku Chin (crescent moon spade) and Ortal Sin (jamadhar) arrive and begin to put pressure on them. However, Ryūto, Renka, Koan Shokatsu and Genson Ryu, Renka's fellow disciples, also arrive and attack the enemy reinforcements. Once Ryuto tells them what to do, Thor fights along side the alliance against Ortal Sin.

They all defeat the masters as after the armed forces retreat, they celebrate their victory.


In the Epilogue, Thor, along side Tsuji and Siegfried, start a rock band and become a huge hit.

Battle LogEdit

Battles PresentEdit

  • vs Kenichi (loss)
  • vs Odin (loss)

Team BattlesEdit

  • with Mizunuma, Takeda, Kisara, and Freya vs. Black Force Team (won)
  • with Freya and Takeda vs Shō Kanō (loss)
  • with Hermit, Siegfried, Kisara, Takeda, Freya, and Niijima vs. Fortuna (won)
  • with Takeda, Kenichi, Miu, Kisara, and Ukita vs Yami weapon's division (won)
  • with Miu vs Rimi (no winner, Rimi left after the disk was destroyed)
  • with Kenichi, Miu, Kisara, Takeda, Ukita, Chikage, Freya, and Siegfried vs Ishida (interupted by Sakaki)



Artwork of Thor in the video game

  • Thor shares many traits with Edmund Honda from the Street Fighter series, among them that they are both Sumo wrestlers who wish to prove the worth of Sumo as an actual combat art.
  • He is named after Thor, the Norse Thunder God.
  • When he's challenged he usually proclaims "For all the fat men in the world!".
  • When Matsuena was looking for a civilian name for Thor he asked his readers to submit names they thought would fit him. His name was chosen from these submissions.
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