Mikumo Kushinada (櫛灘美雲, Kushinada Mikumo) is the Jujutsu Master as well as the Bewitching Fist of Yami's One Shadow, Nine Fists, the Master and also foster mother of Chikage Kushinada. It is worth noting that she was the only female member within the Nine Fists.
Mikumo is a curvaceous and very well-endowed woman who appears to be in her mid 20's. This is most likely due to her family's experimentation on their bodies to slow down their aging process. She has been seen driving in a sports car (clashing with her Japanese style hakama) towards a destination presumed to be Diego's location not long after Diego transformed into the "Angry Steel Fist". She has long waist length black hair, wears an open Kimono to show off her bosom and usually wears a wooded bead necklace around her neck. In her youth, her hair was shorter, down to her chin and she was slightly shorter.
Mikumo is one of the most emotionless and serious members of Yami shown. She rarely shows any emotions other than surprise and always keeps a melancholy face. She believes keeping emotions in control is important for battle and that losing one's temper will dull one's skills. With Chikage, whom Mikumo treats very well, more so than any other member of Yomi (aside from Sho), possibly because she's her disciple and seems to treat her as her own daughter. However, her relationship with Chikage at times is not as maternal as it would appear, as Mikumo is more focused on turning Chikage into a ruthless killing machine rather than as a person. After she personally witnessed Chikage crying over having hurt Ukita and Kisara, Mikumo knocked her out and attempted to brainwash her into becoming a ruthless killer because she wanted to "break" her. She was also very angry when Chikage abandoned their plan to help the pride of their masters rather than kill the Shinpaku Alliance, even going as far as to leave fighting the Ryozanpaku masters just to stop her. She seems to be fond of meditating, as she tends to meditate when she has free time.
In battle, she is very ruthless, showing little to no mercy even to a fellow Yami member such as Diego Carlo and even attempted to kill him and his disciple Rachel Stanley when they both were defeated and could not fight anymore. However, she does have some honor, agreeing to a 1-on-1 fight with either Sakaki or Shigure. She has a habit of referring to others, regardless how old they are, as brats.
Mikumo also has little to no sense of comradeship, as when Sai Kagero joined the side of Ryozanpaku, she had no qualms in viewing him as a traitor and brutally murdering him just to prove a point.
Despite being one of the most powerful masters in the series, she has no problem using petty tactics such as threatning the Ryozanpaku masters with giving orders to Yami control room to have Shigure executed should they interfer with the plans. This act of hers deeply enraged Cyril Rahman to the point that he launched a devastating attack at Kushinada while criticising her with the fact that she is willing to use such a dishonorable and cheap tactics to win the war. It should be noted that her behaviour drove Cyril Rahman to switch sides and become an ally of Ryozanpaku.
Mikumo holds the belief that empathy is weakness and that the strong do not let their heart be shaken by the weak. She used this to her advantage to make Ethan Stanley fight more ruthlessly against Kenichi to save his sister. However, she acts oddly feminine when she recounts her past adventures with Hayato, chiding him for being "hardly charming", covering half of her face with the sleeve of her hakama, and referring back to the events as "the hot fires blazing between us".
Upon witnessing Agaard, Sougetsu and Cyril ally with Ryozanpaku, Mikumo finally lost her calm emotionless demeanor and reacted in frothing rage. She then choose to willingly move ahead with the plan solely because they were provoking her.
Mikumo was her mothers disciple and the creator of the style of martial arts that she uses today. Mikumo has worked with Hayato Fūrinji against Yami in the past, and a flashback reveals a much younger Hayato and what appears to be only a slightly younger Mikumo on the battlefield. It was hinted that the two may have shared a deeper relationship at one time, though Hayato denies this, saying that "the only things that burned were the forts and tanks". It is currently unknown what turned her to the path of Yami, but it has been heavily implied that it happened after seeing the aftermath of the previous Eternal Setting Sun. At some point, she took in and started training Chikage Kushinada as she is the youngest High Class Disciple. Like the other members, she participated in the joint training of Sho Kano, as the sole successor of Yami.
She is undeniably one of the strongest masters of Yami and even the One Shadow Nine Fists. She is able to engage in a battle against both Sakaki and Shigure simultaneously and neither Sakaki or Shigure were able to land any hits on her. She could easly pin-down Shigure with virtually no effort in a one on one fight and finished while sustaining only one cut on her clothes and even then the attack was only successful because she was momentarily distracted. Also, according to Sho, Mikumo posseses a technique that is very similar to the Ryusei Seikuken. Even against a direct kick of air from Silcardo Jenazad, she expresses completely no change in emotions and lightly commented about Silcardo's short temper. She can kill 11 Jujutsu Masters without needing help, killing them with one move.
- Master Judoka (Kushinada Style Jujitsu): In a battle against various jujutsu masters in Battle 307, it is shown that all conventional jujutsu styles are founded on the principle of utilizing of 30% raw power and 70% of skills when executing a jujutsu move. However, Mikumo utilizes style use's no raw power at all (0%) and focuses her style entirely on skills (100%), because of this she is able to not only outmanuneuver most of her opponents, but is able to shift her center of gravity and the gravity of whoever she fights, causing her opponent's to basically throw themselves. Kenichi described her technique as 'Zero gravity'. It's revealed when underwater that she is able to control gravity around her to such as extent that it allows her to float on the water of a swimming pool. She was able to fight against two members of Ryozanpaku by herself and keep them both in check during the battle.
- Impeded Aging: She is far older than she appears, as her mother was thought to have been born more than a century ago and she even called one of her opponents, who was quite old, possibly in his 60's, a "youngster." This indicates that she is possibly well over 80 years old. But she is actually much older, she reveals that she is the founder of the Kushinada Jujistsu style when questioned if she is the daughter or granddaughter of Kushinada Mikumo. You also see flashbacks of Furinji Hayato and Kushinada Mikumo fighting together during WW2. So at this point she is a master class fighter capable of fighting alongside the legendary superman Furinji Hayato over 80 years ago, so she must have been at least 40-50 years old at the beginning of WW2. This makes her the oldest members of Yami. According to Akisame this long lifespan and enduring youth probably involves a strict diet that the Kushinada Style follows.
- Immense Speed: She was shown to be able to "run" on the water at rapid speeds with ease. She was shown to be able to simultaneously fight both Sakaki and Shigure at the same time and outmanuneuver both of them with her speed alone. She is fast enough to make multiple clones of herself and send each clone to fight multiple opponents in her place. He speed is so great is that she's capable of both dodging without injuring herself in the process whereas none of the masters were capable of landing a blow on her. She was shown to be fast enough to escape Kensei Ma "evil hands".
- Immense Agility: Mikumo has proven to be an incredibly agile and flexible fighter, so much that she is capable of blocking on of Akisame's palm strikes from behind her back without turning around and moving her arms behind her with ease. She was able to easily escape Kensei's grip while simultaneously attacking him and Apachai while neither were able to land a blow on her.
- Immense Sei Ki: Mikumo has shown to have a massive amount of Ki to the point where it took on the shape of a larger version of herself. Her ki was shown to be capable of affecting the weather around her, a feat only previously displayed by Ganosuke Yokiou, and inspired fear within non martial-artists despite being far away and not being able to truly sense it. Even Sakaki while facing the giant ki figure questioned whether he was still fighting a human at that point.
She appears soon after Diego's defeat against Kensei Ma and managed to throw him overboard, knock out Rachel, and maneuvered her way passed Kensei Ma, only retreating when elder showed up. Later, she meets up with Hayato and the two reminisce about the days when they fought together. Mikumo then tells him about how much trouble his disciple has been by meddling with Yami's disciples. Hayato just laughs and tells her he won't worry about Kenichi despite her stating the seeds of fear have already been planted.
When Shigure, Sakaki, and Kenichi are guarding treasured weapons at a museam, Mikumo, along with Chikage watch them fight, unaware that her disciple is actually worried about Kenichi's well-being and acts more like a child than a cold fighter. She continually watches over her disciples facial features from her child mode to Yami mode. Having watched enough, Mikumo takes action and tries to fight Sakaki, however, Shigure interrupts and fights her instead. Mikumo leaves with a cut on her clothes and state they'll fight again someday.
While meditating underwater, she is interupted by Jenazad and she informs him about how he can take Miu as a new disciple.
With Jenazad dead, Mikumo and the other remaining members of Yami gather to discuss the matter, but Mikumo said nothing in the meeting. She would later have a talk with Ogata asking if that someone had a hand in Jenazad's influence with the Furinji household thinking someone had a grudge against the invincible Superman. He states he just wants to have an opinion of an elder and Mikumo believes that the aim of the person was to put a stop to Jenazad before he became a chaotic factor of the plan for the eternal sun and walks away.
Mikumo calls all of YOMI together and has them show their skills in front of others not shown to the disciples as shurikens are thrown to them. Mikumo stated this was to show their potential to the others and Berserker is revealed to be with them. After Lugh's fight with the Alliance, Mikumo has Chikage, Hermit and Rachel to help Ogata's disciples in murdering Kenichi and his friends. She states the difference between fights and the fleeting everyday life she had them experience will forge them into a quenching sword and that when the eternal sun sets, one of them will be bound to become a master will appear.
At night, following Chikage's failed attempt to kill her friends due to her bonds with them, she bursts into tears over what she did, prompting Mikumo to enter and knock her out lamenting how she almost broke her into being a killer. As she takes her away, Freya shouts her anger over doing such cruel things to a child, Mikumo responds back that they are the ones causing pain to her, telling Freya to pass that message on to Kenichi.
Mikumo is later seen along side all of the remaining Yami members standing greeting Seitarō Raigō and the rest of the Hachiou Executioner Blade members. She was later seen riding a helicopter with her fellow masters. Upon arriving, she is surrounded by the masters of Ryozanpaku (minus Shigure and the Elder).
When the masters fight together against the Yami masters, Mikumo notices how their breathing is in total sync and have mutliplied their strength doing it. She is then seen together with the rest of Yami preparing to fight, but are stopped when Akisame notes they have no killing intent and, when Honmaki arives to inform them of the Hachiou Executioner Blade members being at the dock and Ryozanpaku realizes it was a diversion. She later leaves with the others after Saiga gives them the message of the beginning of the Eternal Setting Sun.
She was later seen in another country with Mamaduke starting the Eternal Sunset. Upon returning home, Mikumo along with the other members of the One Shadow Nine Fists, comments that cultural exchanges are difficult and Ogata responds that the masters also need to show some teamwork against their enemy. She, along side Ogata, Sougetsu, Mildred, Edeltraft, Marmaduke, Schtilvay, Hongo, Agaard, Cyril, Rin, and Raki all faced off later against the masters and allies of Ryozanpaku. When Akisame demands to know about Shigure, Mikumo confirms that she is alive but states that she nor any of them will go back alive. As Schtilvay prepares to engage them, Mikumo warns him not to underestimate any of them, remembering how well they can fight all together as a group. She then reacted surprised to see that their combo technique managed to injure Rin, Agaard, Schtilvay and even break Mildred's bow. Once all of Ryozanpaku engage them, Mikumo orders everyone to separate them less they get the upper hand. After Edeltraft splits up the masters, Mikumo was seen engaging Danki and Sai in battle.
After witnessing Hongo and Schilvay leave, she loses her focus and allows Sai to cut her clothes and warns her not to take her eyes of her opponents. Kagero Sai and Mikumo are fighting and Mikumo announces that the time for their defeat has come as she produces multiple clones and surrounds Kagero. Kagero unleashes his secret technique but Mikumo evades it, appearing behind Kagero and slamming him into the ground. Mikumo heads towards Danki, who manages to avoid being caught but is hit by an arrow from Mildred. Akisame charges towards Mikumo and aims a palm strike at her back but she catches his wrist and negates the impact of the strike.
Mikumo is on the phone with Saiga to check on the status of their plan. Saiga is seen watching leaders of various countries arguing with each other about the current state of events and he says that it is almost time. Mikumo starts fighting with Ma Kensei, who is also defending himself against Marmaduke and Rin. Mikumo catches Kensei and launches him into a throw when Apachai comes to assist him. Apachai aims a kick at her but she dodges and lands a flurry of kicks behind him, at the same time she manages to appear behind Kensei after he broke free and grabbed her in return. Edeltraft cuts Kensei from behind and the two begin fighting as Mikumo is seen dodging Apachai's attacks. Mikumo states that battle brings out the true nature of people, as she forces Apachai to the ground and the other Ryozanpaku masters are seen struggling against their opponents.
Kagero then falls after an attack from Seitaro Raigou, who wonders how Mikumo has allowed such a turn of events. Mikumo replies that she has not enjoyed a battle like this in a while and says that the Katsujinken masters aren't half-bad, while holding up a defeated Danki.
Apachai charges at Mikumo but is blocked and gets slashed by Raigou across the chest. The other Ryozanpaku masters jump in to help with their combination attack but are stopped by a combination from Mikumo and Raigou. Akisame wonders if the Satsujinken have managed to work together but Mikumo says that Raigou is familiar with Katsujinken techniques and thus was able to synchronize with Mikumo. The Ryozanpaku masters are surrounded by the Yami masters and Mikumo announces that the end of the battle is coming.
Just then, Mikumo talks with her disciple over the course of the battle. Mikumo is telling Chikage to return to their strategy of overwhelming the Katsujinken and to follow her order. Chikage replies that in the time she spent in Kōryō High School she has learned that there are times when going against someone's will works out for their sake; she has decided that fighting unfairly will end up ruining their pride as fighters and so Chikage is doing what she feels is right, adding that Kenichi has showed her that path.
Mikumo grits her teeth angrily because of her disciple's behavior and asks her fellow masters to control things at the disciples' battlefield. Deciding that it would be better if she went to the other battle herself, Mikumo seeks to end the battle against the Ryozanpaku masters. She causes an opening for the armed division to land a fatal blow on each of the masters but Akisame unleashes his true strength and manages to catch all the weapons before they land. However Seitaro Raigou appears behind Mikumo and aims to stab Akisame, who is unable to dodge the attack.
Kagero Sai regains consciousness and blocks the kodachi with his hoe and lands a punch on Raigou as well, resulting in Mikumo to express shock for the first time in the series. After Sai expresses how he wishes to help the Katsujinken fight for good and save the Satsujinken's pride, Mikumo kills him, enraging the Ryozanpaku masters.
After witnessing Agaard and Sougetsu change sides Mikumo tells Ogata that the "setting sun" must happen at all costs and vows to use every means at her disposal. She threatens the Ryozanpaku masters with killing Shigure if they continue to resist against them. Rather than standing down, the masters are further angered and says that Shigure has been prepared for that possibility, as sacrificing one's life for the sake of others is the very principle of Katsujinken. Mikumo is surprised by the strength of their aura and asks for Cyril Rahman's help to divide them before Ryozanpaku combines their powers. Cyril suddenly attacks Mikumo and she is forced to evade and regroup behind Raigou.
Cyril insults Mikumo for bringing shame to Satsujinken by hiding behind a prisoner. Cyril questions Mikumo for debasing the ideals of "Eternal Setting Sun" seeing how she has been training Chikage to become merely a weapon for fighting. Mikumo remarks that their aura reminds her of something as she imagines Hayato Furinji. Assisted by Cyril's mantra, the Ryozanpaku masters (along with Sougetsu and Agaard) stage a counterattack against Yami as Mikumo, furious, calls them brats who aren't familiar with the previous "setting sun".
After Mikumo hears about the arrival of the previously defeated masters (Diego and Alexander), she appears exasperated that these "brats" just keep going against them. She announces that it might be earlier than planned but it is time to move on to the next phase of their plan.
The Ryozanpaku masters, along with Cyril Rahman, Ma Sougetsu, and Agaard are seen to have many injuries throughout their bodies as they face down Mikumo's group, with Mikumo's aura bearing down on them.Mikumo unleashes her technique (Kushinada Style: Thousand-Year Throw) as she slams the ground with her hand, causing many hands made
After all of the Hachiou members (except Seitaro) are defeated, Mikumo, along with Seitaro and Ogata, face off in an epic clash with the Ryozanpaku masters whihc results in a large explosion occurs at the masters' battlefield as the colloding auras cause a yin-yang symbol to form in the sky.
As the battle drags on, Mikumo notices the missle launch and gleefully states its their victory. However, this is short lived as the Elder arrives and destroyes the missle at the last second. Realizing she lost, Mikumo retreats but not before Kensei strips her of her clothing as a last insult.
Her whereabouts after the Eternal Sunset are unknown, as no one, including her disciple, Chikage has heard from her since.
In the bonus chapter, she meets with the Elder discussing about the battle that has happened, with the Elder stating that he will stop her as long as he's alive. He then asks her to buy him Anmitsu as part of their promise made years ago.