Shigure Kōsaka is a weapons master of the Ryōzanpaku, as well as the youngest master of Ryōzanpaku and only female master.
As a child, Shigure's appearance was so boyish that even the immensely perceptive Akisame mistook her for a boy. As an adult, Shigure is a fairly tall and beautiful young woman with a slender frame yet remarkably curvaceous-figure and well-endowed breasts. She has long waist-length raven hair usually tied back in a high ponytail, peach skin, and light purple eyes. She wears a purple choker around her neck that contains numerous small pins. She normally dresses in a small pink kimono and long purple stockings; underneath she wears bandages over her chest and a fundoshi. When fighting seriously she dons chain mail and wears a black strap under her breast to kept the chain mail in place. Her most eye-catching feature are her eyebrows which resemble lightning bolts. She is almost always seen carrying her father's last and finest ever sword; a tsuba-less nodachi strapped to her back with makeshift grip of bandages wrapped around the hilt.
Shigure believes that weaponry should be seen as more than just a tool, that it should be seen as an extension of the body: simply relying on the weapons strength alone will not make you a master of it. She seems to have a great deal of love towards weapons, as at one point during the DofD arc she asks to keep a tank, treating it like a pet and even naming it 'Little Cattaleya'. Likely due to her emphasis on the Katsujinken, most opponents she faces end up losing without significant injury or by simply having their clothes torn (which she often does to Miu and Freya's Valkyries). She seems to be aimed at women probably due to the fact that more times than not, women will stop fighting and try to cover themselves up. Even during fights with dangerous opponents like Kagerō Kii and Mildred Lawrence, she will not resort to lethally slicing or slashing the opponent's body, instead opting to using the back of her sword, and in extreme situations, shallowly cutting or attacking an opponent with a weapon to the point that they have small, non-lethal flesh wounds and cuts.
When initially introduced she appeared to be a loner, often avoiding interaction with the other members of Ryōzanpaku (besides occasionally Apachai). At the same time, due to her unique childhood experience with Akisame, she has developed a strong respect and loyalty to him, at times seeing like a surrogate father, as she will follow his requests without question. She will usually retaliate violently to Kensei's perverted antics much like Miu. However, she still has a feminine side, blushing in reaction to Akira Hongō refusal to fight her for being a woman and showing she was grateful for someone considering her as a woman and again when she was stripped naked during her capture by Yami and blushed calling the scientists in front of her perverts.
Shigure is known to occasionally pause between words when talking. She is usually seen with an emotionless demeanor, rarely ever smiling. She is usually seen smiling when proud of Kenichi's progress. She was even cheering happily when Kenichi imitates her while battling Odin and copying her fighting style like the other masters. Shigure also has a great love of animals. Her best friend is her mouse Tōchūmaru and will not forgive anyone who hurts him.
Shigure seems to have sleeping issues, as shown by Sakaki that she sleep walks and mutters some words in her sleep that Sakaki states is creepy and somewhat scary, making this the only things he's afraid of.
Shigure's behavior has changed noticeably since Kenichi's arrival, as noted by Miu who once wondered if Shigure sees him as more than her disciple. She begins opening up to the others, and even joins them for meals. She become's indignant when the other members of the dojo express relief that Kenichi was alright after a training trip with her, though this could be due to her taking their relief as insult to her mastery. Shigure even allows Kōetsuji to tell Kenichi of her past and is quite candid around him. She would even bathe right next to him, unconcerned with him seeing her nude and even suggests that they bathe together again. Out of all the masters, Shigure trains Kenichi the least, yet it is implied she yearns to train him, and is disappointed with Kenichi's reluctance (and fear) to use weaponry but often tries to convince him to train more. When she finds the ability to give Kenichi words of advice during her task to revive Kenichi as a martial artist, she pumps her fist triumphantly for succeeding as a teacher to Kenichi.
There's a running gag that Shigure has shown to have no modesty in the slightest, causing others to be uncomfortable (or pleased) and that usually ends for trouble for others. Such as when Kenichi went to wake her up from a mission she had, she barely had anything on and caused him to gain a nosebleed. She even wanted to bathe with Kenichi, showing no discomfort at all and even fought several opponents naked and not even embarrassed by it. When she fishes for food on her own, she is naked and not uncomfortable at all. She is even fine with undressing in front of others such as Kenichi despite his protests (and Miu covering his eyes). However, she does have some modesty, as she was somewhat embarrassed being naked in front of the Yami scientists.
Shigure is first introduced when Miu brings Kenichi to Ryōzanpaku to train. At first, Shigure didn't think much of him, and continued to be a loner from everyone else. Eventually, Kenichi asked her to train him and she agreed (she pumped her fist in happiness). She trained him to fight unarmed without weapons and how to use them if needed.The Valkyries, Tōchūmaru signals her (due to him having followed Kenichi) and she arrives to fight and easily defeat them with just a wooden spoon and tears their clothes to almost nothing. When Kenichi fights the leader of the Eight Fist League of Ragnarök, Ryūto, Shigure gives a happy expression when Kenichi mimics her fighting style with the other masters.
After Ragnarök is defeated, the masters now must deal with Yami. When the Elder mentions to Shigure alone that Miu's mother was killed in a snowstorm, Shigure is shocked. At some points, Shigure would go on trips to find valuable swords and try to find her fathers sword, and when she returns home, she would usually go to bed from traveling all night. Shigure would allow Akisame to tell Kenichi about her past stating if it's him, it's alright.
Around the time of the D of D tournament, Shigure would fight Female Weapon Guard and win easily. She would even want to take a tank home and call it a "pet" while grabbing it. She would accompany Sakaki to save Jenny Grey, and would act surprised when Jenny asked if Sakaki and Shigure were a couple. They all eventually defeated the enemies and saved Kenichi from getting killed from the soldiers. Shigure would congratulate the Shinpaku members for defeating Fortuna and they all went home.Shinto Gōrenzan the trip and how fun it was to bathe with him (shocking Miu and Kensei), she wishes to train him sometime again. Miu is angry about the bathing moment and walks away from it despite Kenichi trying to explain, and then, Shigure for the first time, smiles at Kenichi stating his and Miu's relationship is really good and special, surprising him. Miu returned and said she was just kidding and noted Kenichi had a reason and knew Shigure did what she did for a reason. Miu then noted about how Shigure having changed since Kenichi entered Ryozanpaku, suggesting she views Kenichi more than just a disciple, believing she may have feelings for him.
When Rachel Stanley is taken by Junazard, Shigure helps with the other master to save her and defeat the guards there.
Afterwards, when the Yami weapons group would try to steal valuable weapons, Shigure, Sakaki and Kenichi would guard the weapons at their location. They would eventually engage with the enemy and meet Kagerō Kii again and tell him that she destroyed the sword he wanted back, leaving him depressed and unable to fight. When Mikumo Kushinada would try to attack Sakaki, Shigure would step in and fight her and only be able to give her a cut on her shirt. Mikumo left, but stated they'll fight again someday. When Kenichi had to defend the sword they came to protect, Shigure would convince Sai to trade sides for her father's sword and help defeat the enimies and he agreed. Afterwards, they met again and gave him the sword. Since then, he's mellowed out.
When the weapons division comes again but with more danger and having taken Freya's grandfather, Shigure leads the Shinpaku Alliance to save him. She would run into Agaard Jum Sai and fight him, however, even Shigure was no match for him and would have lost and been severly injured if not for her guard vest. She later took Kenichi to watch the other masters praising him for fighting a master class opponent and when he smiled tears of joy, Shigure also smiled.
After heading to Okinawa for Apachai to fight Agaard, Shigure would fight Lance Of The West and win. After returning home, Shigure and the other masters had to disband till the police left their home. They eventually returned home after catching Miu kissing Kenichi on the cheek. Shigure and Apachai would later follow Kenichi and Miu when they want to find out more about Miu's past, but would lose track of them due to them stopping for bento. Thanks to Tōchūmaru, they made it in time for Shigure to fight Akira Hongō, but he refused to fight a woman (though Shigure was flattered that someone thought of her as a woman). After the Elder told Miu about her parents, they returned home.
Following the discovery of a Yami base, Shigure and the other masters head out to the base with Kenichi and the rest of the Shinpaku Alliance. However, they have the youngsters stay for their safety. They arrive fighting Ogata's men and Shigure comments she can't detect him and for everyone to be on their guard as they split up to find him. They all search and find nothing and regroup noting he's not there. Shigure then goes back to check on the Shinpaku Alliance telling them about not finding Ogata and that she came back to check on them sensing a Strong presences. Later at night, she listens to the elders talk with Akisame and is left shocked discovering of Tanaka's wife also being killed by Ogata along with his unborn child.Kagerō Kii, who gives her bags of dirt and a device for extracting iron sand from the dirt and sand that she gathered. It was then revealed that the reason for this was for her to forge the iron sand into metal, which she can use to provide arms for the alliance. She states that she's really forging armor for protection and says it will take a week to make and that Miu and Kenichi should leave. When Kenichi says he'll stay, Shigure, though touched, says the best he can do is train less he choose to fight with Apachai and Kii. After the week is up, a sleeping Shigure and Apachai arrive at the Shinpaku Alliance headquarters and Shigure slashes Miu's outfit up out of self-defense. She awakens and reveals her new arm guard for everyone and tests them by attacking them all, to which they're amazed that they are uninjured by her attacks.
At Ryōzanpaku, Shigure and the others are visited by Inspector Honmaki and are shocked to hear how he and the entire police must guard Yami at a governmental institution prompting Shigure to note they don't need protection and something is wrong. Regardless, she and the other masters are all determined to put them away in Big Lock. As all the masters prepare for their battle against yami and the government, Shigure prepares by sharpening her sword then dulling it again to make it more battle-ready. The other masters decide to leave Shigure with Kenichi and Miu in case the armed members of yami decide to move. Kenichi begins to complain about how reckless their actions are, to which they say that as martial artists they have to stand by their beliefs to the very end, with Sakaki even saying that one day Kenichi would be standing side by side with them. When Miu tells Kenichi that he'll have to protect her first before that day comes, Shigure jokingly says that he'll have to protect her too.
Later as Kenichi trains she watches the news and is shocked as she sees someone she recognizes. When Kenichi asks who he is, she states he's a murderer and that he's likely using one of her father's weapons and that he's used them the most to kill people. As she questions whether she should go after him or not, Kenichi and Miu encourage her to go, which prompts Shigure to bring the both of them along. She states that if she leaves them behind the Yami masters will likely go after them stating her solution is brilliant.
At the Tokyo docks, Shigure and the others arrive in secret from the guards and tells Kenichi and Miu to stay close no matter what. As she smells blood, they find bodies noting they're still breathing. She notes that since their still breathing it has to be his work and states that the person leaving them alive to make the stage grander is the work of Mihai Știrbey. Once they find the boat he's on, Shigure and the others board it with her weapons just in time. Just then, she's shocked to sense not one, but seven kis on the boat, realizing all of them belong to the Hachiō Executioner Blade members.
While Kenichi wonders if they should still hide, Shigure notes there is no point in doing so since the armed members have likely sensed them. She then shouts out Știrbey's name noting he's watching them. She introduces herself to Știrbey and appologizes to Kenichi and Miu that her plan to protect them backfired and will have to fight the armed group with her life on the line. However, as Kenichi refuses to do so being her disciple, and Miu agrees with him, Shigure is moved noting his growth, but orders him as her master that he finds a way to escape. As she faces Știrbey, she asks if she can trust that he won't go after Miu and Kenichi. While Știrbey says his friends won't, but he will gladly kill them both, Shigure notes she just has to make sure he can't fight anymore and will put her life on the line as she faces Mihai Știrbey alone.
Shigure begins to do battle with the Hachiō Executioner Blade, powering up her ki and getting commended by Mihai Știrbey. Shigure begins her attack with Shinto Gōrenzan and proceeds to attack all the members of the Hachiou Executioner Blade at the same time. Seitarō Raigō insults Shigure's decision of taking them on all at once while Kenichi and Miu seek to escape, understanding that Shigure is distracting the opponents away from them. However Mihai Știrbey appears behind them unscathed due to protective clothing made by Shigure's father. Știrbey warns Shigure not to move and says that today is an important day for them and a black flag appears on the ship, signaling the Eternal Sunset. Shigure then questions what they are carring on the ship and slashes it to find gold bars for their military fund.
Shigure and Mildred Lawrence are battling. The female archer attacks Shigure with her arrows but Shigure manages to dodge them using her immense speed. The bow master dodges Shigure's counterattack (mocking the Katsujin-ken in the process) and shoots an arrow at Shigure, who catches the arrow with her fingers. Shigure then takes hold of her opponent's bow and shoots an arrow in the archer's stomach using Kosaka-Style: Kagamibanare.The bow master catches the arrow before it hits, but is visibly angry at the fact that she was attacked with her own weapon. As Kenichi and Miu attempt to escape, Michael again blocks their path and decides to kill them, to which Shigure begs him not to and attempts to save them. However, they are saved by the arrival of Christopher Eclair and Mycroft. When Christopher calls Sakaki over how he wants to be paid, Shigure hands him a gold bar and he and Mycroft assist in fighting the armed users. Christopher, Mycroft, and Shigure group together and Shigure requests that the other two escape with Kenichi and Miu. Christopher asks what she is planning to do against the powerful enemies if they run and Shigure responds with "Please." prompting serious looks from Christopher, Kenichi, and Miu.
She uses the Kōsaka style final technique, Sōto Kyōrenzan wich helps her keep all 7 hachiou at bay by controlling their weapons, with that Christopher, Mycroft, Kenichi and Miu escape the ship but Shigure is defeated by the seven master, when she is about to get killed by Edeltraft von Schiller Rin Tachibana stops him revealing that Shigure father is Yami´s missing blacksmith and that they need her alive.
Shigure is later taken prisoner by Yami and isolated in a room and and her hands and feet are bound by an unknown material while stripped of her clothing. A scientist from Yami is talking to Shigure and asks her to help them make weapons. The scientist understands that pain would not make Shigure cooperate (she has been calling the scientist a "pervert" and a "sicko" throughout his speech) but when he threatens to harm Kenichi and Miu she grows quiet. The scientist notices a choker around Shigure's neck and rips it away, revealing needles hidden in the fabric. Shigure takes the needles in her mouth and shoots them at the scientist and his colleague, who fall unconscious because of poison in the needles. She shoots needles at the restraints on her feet and manages to break them to the surprise of the guards. They shoot at her but she dodges and her hand restraints are freed from the floor. She grabs the broken Yami-crafted blade in her mouth and defeats the guards.
A guard is about to shoot at Shigure but he is disarmed by a tiny spear thrown by Tōchūmaru, who Shigure is happy to see. Tōchūmaru uses the machine gun against the other guards (to their surprise) and Shigure charges at them, slicing their guns in half and pulling off the pins from a guard's grenades using her toes. She cuts a pipe and runs away from the explosion, causing the soldiers to exclaim Shigure is like a "witch" as she destroys the base. A guard shoots at Shigure but she is able to use the bullets to break the restraint connecting her hands and punch the guard to free her fist. She uses the stolen blade to free her other hand and asks Tōchūmaru how he found her and ties up her hair with the ribbon from Tōchūmaru's tail (which she gave him when they first met). Someone from behind Shigure asks if the mouse is indeed Tōchūmaru, and the Hachiō Samurai appears covering Shigure with clothing. Shigure is surprised and questions how he knows Tōchūmaru.The Hachiō Samurai does not answer, telling her to surrender because it is impossible to escape. Shigure takes a fighting stance with the broken Yami blade she has stolen and the samurai states that he would have to hurt her to subdue her. Shigure charges in towards the samurai and they exchange a flurry of strkes. The samurai compliments Shigure on being able to do so much with only a broken blade, as she is able to jump over him and prepare to escape. They continue to fight as Shigure uses her Kōsaka Ryū: Tsumujikaze. As the attack is about to hit the samurai, he is able to parry the blow using a technique from the Kōsaka School as well, Kōsaka Ryū: Yoroigaeshi. The samurai is able to break Shigure's blade but she grabs a weapon from the samurai's quiver, using it to break down a wall. The samurai is surprised that she was able to steal a weapon from him and Shigure asks the samurai to reveal himself. He says that she has gotten stronger that he had expected and he takes off his helmet. Shigure is surprised as the samurai's face is revealed as Shigure is shocked to see he is her own disciple brother. Rin then takes advantage of Shigure's shock and begins attacking. He reminds Shigure that in the past he had told her if she became extremely skilled with weapons that they one day meet again. They continue to fight till they reach outside as Shigure sees a large amount of military forces for Yami as Rin explains that Yami has gathered power from all over the world and asks that she joins them, but she remains unresponsive.
She is later imprissoned again forced to make weapons, however, her blades break after being touched in a certian area. She has guns all around her but smirks saying it was an "accident". She's thrown into another prison and hopes the others at Ryōzanpaku are safe. Later, she is seen building various metal items from a dumbell, a piggy bank, and a spork. The Yami scientists are angered because she is not making weapons and all the tools are blunt (including a blade that was soft and wilted). Although she is mocking them, they are astounded with her crafting ability and they are unable to analyze her technique. During this conversation Shigure attempts another escape, using a flail and a soft iron blade that she was tempering. The head Yami scientist notices an item around Shigure's waist and remembers that one of the guards had their watch stolen earlier. They realize that Shigure has assembled a sextant using the watch and she jumps out the window and uses the sextant to locate her position. Shigure throws away the sextant just before a plane appears to capture her, but as she surrenders she hides a smile. She is once again bound in the special resin to hold her down until she feels like cooperating.
The next day Shigure is seen is seen instructing the scientists of the weapon team. The head scientist asks what is going on and a scientist responds that they have failed to make weapons despite perfectly copying her procedure, concluding that they need to train their spirits to learn the secret of the truth of steel. The head scientist reacts that the others are suffering reverse Stockholm syndrome: the scientists are indeed improving their technique in making weapons but they are also beginning to think that making killing weapons is wrong.At nighttime a guard passes through Shigure's cell and confirms everything is normal. Shigure's bonds are shown to be cut in half as she escapes from them and goes through a hatch that has been cut through her cell. As she continues her escape it is announced that the Hachiō Executioner Blade has returned and the soldiers are assembling to report to them. Tōchūmaru beckons Shigure as he has found a satellite phone, which seems to be the one that Rin uses to contact Kiyoi Kidō, while a confused Shigure wonders how to use the satellite phone.
She calls various people, but no one who she can give her location to. Luckily, she contacts Kiyoi Kidō, Rin's younger sister. Kiyoi informs the Ryōzanpaku masters along with Kenichi, Miu and Niijima who are present, surprising Shigure. Just as she gives her location, she is ambushed by Știrbey, Mildred, and Raki who attempt to destroy the phone. Shigure gives her coordination's to the others and tells Kenichi to become strong just as the phone is destroyed. Shigure is then promptly captured again afterwards. She is then later visited by Satomi Kajima, who is embarrassed as seeing Shigure naked and places his coat over her. When Shigure asks who he is, Kajima formally introduces himself having stated his master allowed him to speak with her and asks about Kenichi being the "strongest disciple" of Ryōzanpaku, to which Shigure says that's wrong and he has no talent at all. Kajima smiles and states he's happy to hear this due to him being the same as he to had no talent and worked hard in numerous battles to reach his level of skills. Just then, Shigure notices a key in his jacket and asks why is he helping her escape, to which Kajima replies he's following the orders of one of his masters, and how it would be a waste to kill someone who won over the weapon research division (who agreed to spar her due to a petition). As he walks away, Shigure notes how he reminds her a lot of Kenichi.
She later escapes thanks to Kajima, and manages to find her sword during the confusion. Shigure later appears to rescue Niijima from armed guards. A man within the control room orders the entrance to be sealed off but Shigure blocks the closure with her sword and knocks out the people inside the control room. Niijima goes to a computer and prepares to install the virus and Shigure senses an opponent approaching, just as Saiga arrives and sees that the control room has been breached. Shigure removes her sword so that the wall can close before Saiga reaches them.
It is announced that there is five minutes left until the missiles launch and Shigure is listlessly waiting in the computer room while Niijima is uploading the virus. Shigure asks if the virus worked but Niijima shouts at her and says not to distract him (as she is still half-naked) so Shigure and Tōchūmaru sit quietly against a wall. She stands up as she senses a powerful ki on the other side of the wall, wondering what may be happening on the other side. After Saiga and Senzui break through the wall, Kenichi finally sees Shigure and is overjoyed at their reunion, but Shigure warns him to not lose focus as he is still fighting Kajima. Shigure remembers how Kajima helped her escape and so she respects his duel with Kenichi and encourages her disciple to fight proudly.
As she watches her disciple fight, Shigure asks if Kajima is worried about his two masters fighting. Kajima dismisses Shigure's concern and expresses his delight in that his masters' battle will result in further development of martial arts.
An announcement says that there are two minutes left until the missiles launch and Niijima has found a computer to complete the virus upload. Shigure tells him to hurry as they have been discovered by the enemy and she is seen fighting off a wave of enemy troops. As she continues to fend off the enemy troops she watches Kenichi's fight with Kajima progress and reacts shocked to see Kajima use Shinogidachi throughout his whole body.
As Kenichi is struck by Kajima's Kia Shinogidachi, Shigure notes that his move cut off all his ki as she calls out to her disciple. Luckily, Kenichi regains consciousness and successfully blocked Kajima's Shinogidachi as Miu and Shigure are amazed by Kenichi's progress, who managed to surpass the "releasing" of ki and reach the level of "holding" ki. She then tries to stop Kajima from using Kai Shinogidachi again stating it will kill him if he uses it again.
After Kenichi defeats Kajima, Senzui and Saiga's battle reaches to them as Shigure tells Miu to not interfere and she would die if she tried to get involved. Just as Saiga reveals he stole Senzui's remote detonator for the missile launch, Schtilvay arrives and attempts to kill Saiga and take the detonator despite Saiga's pleas that it will bring nothing but chaos. Shigure saves Saiga and defeats Știrbey with her Shinto Gōrenzan while destroying the scythe her father made that Știrbey used to kill so many people.
After the elder shows up to destroy the missile, Shigure stares in horror. Luckily, he survives as she and the other alliance members celebrate the defeat of Yami. She is also shown looking at Kii's broken hoe, possibly saddened by his death.
In the Epilogue, Shigure continues her daily activities training Kenichi as she later learns that Kenichi's novel he wrote became a best seller and won an award to which Shigure realizes he used the adventures of Ryōzanpaku in the story, to which other people believe non-fiction.
- Weapons Master: While being the youngest master of Ryōzanpaku, Shigure has repeatedly proven herself to be a formidable person to face. As the successor to the Kōsaka-Style and having mastered at such a young age, Shigure has remarkable mastery of all forms of weapon combat, earning her the title of "The Prodigy of Sword and Mistress of all Weaponry". Even with dull utensils such as wooden spoons, her attacks have shown lethal might behind them. With remarkable dexterity, she is even able to wield weapons with her feet as effectively as her hand. She is one of the few that has reached the highest level of swordsmanship, "to fuse with their sword." In all the fights she has been in, she has yet to be seen receiving any major injuries even against other master-class weapon-users. She is able to fight off multiple armed and unarmed opponents of different styles with ease, even fend off seven grand masters of the Hachiō Executioner Blade of Yami, seemingly she was only defeated from her divided focus on allowing Miu and Kenichi to escape. During her imprisonment of Yami, she was completely stripped of any and all materials in fear her talent to turn virtually any material into a weapon. After breaking free, she completely overpowered the guards with a small amount of weapons and tools that were around her, leading the guards to believe that she is a "witch".
- Master Blacksmith: In addition to her knowledge and skill of weaponry, Shigure, like her father, is an exceptional forger of metal and weapons, having gathered sand and dirt to mix together, while using a metal flow of water in a nanna naga, to make iron sand and gather all the iron in the minerals. Shigure also seems to understand the more complex forms of metal working, able to make protective gear using the same method for making blades which was durable enough to withstand a sword slash from a weapon-user of Shigure herself. She also understands multiple other forms of metal working, able to produce similar results for any necessary gear. Her knowledge of metal and the refinement of it are comparable to her late father, making her a highly desired war tool for Yami as even their advanced science for metal forging proved obsolete compared to Shigure's skill.
- Master Ninja: Keeping to her ninja-like attire, Shigure is highly sneaky when she wishes. Constantly, she is seen appearing from seemingly nowhere without making a sound. Shigure has also used various camouflages to disguise her presence. Her stealth makes her a brilliant spy and possibly assassin as since she perfectly mask her presence, only the most skilled of masters can detect her thus allowing her to assassinate many lower level enemies should she want to.
- Master Unarmed Combatant: While a weapon-specialists by trait and preference, Shigure has comparably impressive skills at hand-to-hand combatant. During her imprisonment of Yami, while having access to no tools and her hands completely immobilized, she could easily fend out several guards with powerful kicks and sweeps. With her fists, she can launch powerful punches able to smash through their protective helmets.
- Innate Talent: Living up to one of her nicknames, Shigure since childhood has shown remarkable athleticism and skill with any tool in her hand. She could skillfully dive for fish and hit any moving target she desired as a means of fun. During her first time wielding an actual weapon against actual warriors, she left the men in awe at her ability to skillfully wield a blade more than twice her height. After her father died and she was raised by master of the Kōsaka-style, she quickly mastered all he had to teach, greatly impressing the old master. In battle, she has been able to easily overwhelm most weapon-masters at least twice her age. Just like how Apachai can quickly master and can become an expert in an activity outside of martial arts like othello once he puts his mind into it to beat Honoka, Shigure can quickly master a skill outside of martial arts through diligent practice as by repeated rehearsal she managed memorize all of her lines and information in acting as Shizuha Fūrinji when Miu's teachers visited the dojo for an inspection. Once there she was able to put up a convincing act as Miu's mother while Sakaki struggled to maintain his character as Saiga Fūrinji despite having the same amount of practice as Shigure though Yasunaga was able to see through the act due to his large experience in meeting and interviewing the parents of his students.
- Immense Speed: Shigure's attacks in battle are shown to be remarkably fast as most people cannot follow the number of strikes she launches. Even when her guard is down, she can in an instant unleash a large flurry of attacks with no wasted movement. The speed of her attacks is so great, that while playing an interactive sword-fighting video game, she discovered that she had to hold back considerably for the system to register her moves. On her feet, Shigure can outrun most cars and is able to easily jump from vehicle to vehicle. Shigure has displayed enough speed to easily defeat an entire group of armed soldiers in an instant. She was able to defeat Kagerō Kii, a sword master, so quickly he didn't even realize she had moved. She was fast enough to attack all seven members of the Hachiō Executioner Blade simultaneously, despite being outnumbered against them.
- Immense Agility: Shigure has demonstrated remarkable grace and balance even while performing the most basic of tasks. Regularly at home, she is seen practically climbing all over the walls to get around. In more extreme cases, she can jump across town from rooftop to rooftop, never losing control.
- Immense Strength: Despite her lithe frame, she is very strong and can cut through highly durable substances. She once cut off the cannon of a tank with her sword before jamming the cannon into the tank's side with her bare hands.
- Immense Accuracy: Possibly her most remarkable skill, Shigure has perfect aim with any tool she handles. Even with frail or dull-edged items, such as a spoon or faulty blade, she can strike without hitting any vital points. With projectiles, she can precisely hit any speeding and squirming target from a considerable distant. At close-range, Shigure strikes can skillfully cut through targets with such precision, the sliced target can momentarily appear unaffected. Her precision was also able to destroy Boris's boots when the Sambo disciple invaded Ryōzanpaku without harming his feet or neatly split a leaf in half on its flat side.
- vs Kagerō Kii (interrupted by her father, though he states that she would have lost)
- vs The Valkyries (Won, only destroyed their weapons and tore off their clothes)
- vs Female Weapon Guard of D of D tour. (Won)
- vs 10 Experts and 4 masters (won)
- vs Kagerō Kii (Won)
- vs The Valkyries (Won, only destroyed tore off their clothes again to protect them from Yami)
- vs Kukuri User (Won)
- vs Mikumo Kushinada (Undecided)
- vs Agaard Jum Sai (Undecided)
- vs Spear of the West (Won)
- vs Akira Hongō (undecided)
- vs Mildred Lawrence (undecided)
- vs 7 members of the Hachiō Executioner Blade (Lost, but allowed Kenichi and Miu to escape)
- vs Yami guards (Won)
- vs Rin Tachibana (undecided)
- vs Raki Hoshinano, Mihai Știrbey, and Mildred (Unknown)
- vs Yami Missile Guards (Won)
- vs Mihai Știrbey (Won)
- The character Kamui Tokinomiya from the Arcana Heart series is based off of Shigure.
- She is the only master of Ryōzanpaku to have not completed a battle against a member of the One Shadow Nine Fists.
- In every real fight with real master class fighters she has lost part of her chain mail.
- She is the first Ryōzanpaku master to be defeated outside of a flashback (although, it was off-screen).
- According to Kenichi, together with Apachai they are the worst possible master-combination as escorts.