The novels frequently describe Mikage as having a very masculine appearance, brought on by years of intense physical training. She has short brown hair and eyes and her usual attire consists of gym shorts, a training top, and a light jacket.
Mikage is shown to be in peak physical condition due to her profession as a martial arts instructor. She has enough raw physical strength to damage concrete and her training has disciplined her to be a very focused and deadly fighter. Her fighting style is one that is studied by a famous martial artist, Traugott Geissendorfer, who owns his own global chain of martial arts schools.
Mikage's personality is described as being tomboyish by others which was likely because most of her time is spent around her brothers. She's usually level-headed but can get easily flustered when her inexperience with romance is brought up. As a teacher, she is shown to be very caring towards her students but also strict enough to keep them in line. As seen in Volume 09, Mikage also appears to be slightly amoral as she has no qualms about killing but takes issue when Izumii attempts to rape an unconscious Mimizu.
It can be assumed that Mikage lead a fairly normal childhood up until her enrollment at Raijin Academy. Mikage started learning martial arts at an early age and was already a proficient fighter by the time she started high school. Soon after the school year started, Mikage took an interest in Izaya Orihara and eventually developed a crush on him. While Mikage would make several attempts to get to know him better, Izaya treated her like another one of his pawns. Eventually, this infatuation would lead to Mikage taking the fall for an as of yet unspecified scandal which would force her to drop out of high school. With no other real options for work, Mikage eventually takes up the family business and becomes a teacher at Rakuei gym.
Mikage as well as her siblings are introduced in this arc. They don't appear to play any significant role until near the end. Mikage gets an invitation to Izaya's office and she agrees to go. While she walks, she encounters Izumii Ran and the two appear to know each other rather well. When they arrive at the apartment they also see Adabashi Kisuke, Haruna Niekawa , and Sloan already waiting for them. Izaya and Namie also enter with Izaya explaining that they are all his friends and invites them to have a hotpot party with him.
Dragon Zombie ArcEdit
Mikage overhears her brother and Izaya fighting outside her dojo and decides to put a stop to it. She berates and severely beats Eijirou for disgracing the name of their gym by starting a fight in public (as well as proclaiming she was raped to everyone within a three block radius). She lets Izaya escape and proceeds to leave before Eijirou stops her again. He asks if she was still interested in Izaya after all that he's done and she simply knocks him out in response.
Mikage appears again along with Izumii, Haruna, and a small group of members of a gang called Dragon Zombie in order to rescue Izaya who had been kidnapped by two groups called "Heaven's Slave" and "Amphisbaena." After Izumii tricks them into releasing Izaya, Mikage and the dragon Zombie members bust in to incapacitate the henchmen (although it was Mikage who did all the actual work). When Izumii incapacitates Mimizu and is about to rape her, Mikage intervenes and threatens to kill Izumii if he goes through with it. Although he leaves Mimizu alone, Izumii threatens to do the same to Mikage. She brushes him off and dares him to try it if he was that confident. Seeing that she was serious, Izumii backs off and leaves. After the operation draws to a close, Mikage simply returns home.
Saving Izaya/ Haruna returns ArcEdit
Mikage, Kine, as well as a few members of Dragon Zombie catch Sloan (who at this point is being controlled by Kujiragi) attempting to carry an unconscious Izaya out of his office. After incapacitating the Dragon Zombie members, Sloan attempts to throw Izaya at Mikage in an attempt to catch her off guard however, she simply kicks Izaya out of the air. Kine and Mikage eventually overwhelm Sloan and force him to retreat through a window. As they go to check on Izaya's wounds, they find out that he has been awake the entire fight and simply pretended to be knocked out.
After the fight, Mikage and Kine urge Izaya to get checked at a hospital as his injuries might be more severe than they think. Izaya initially resists but eventually gives in to their advice. After Izaya had left, Kine asks Mikage about her history with Izaya with Mikage musing on the past as well as elaborating on her feelings towards him.
Showdown at Tokyo Hands Arc Edit
Mikage is chosen by Izaya to stand guard to prevent anyone from intervening in his final fight with Shizuo. Mikage complies as she waits at the staircase leading to the roof. Eventually, Varona and Kujiragi arrive to stop Shizuo from going too far, but Mikage fights both of them at once, stalling their attempts to break through. Mikage acknowledges that she most likely won't win but is confident in her ability to stall them until Izaya and Shizuo had settled things. She is eventually knocked out but by this point, Izaya and Shizuo's fight had already spilled into the streets.
Durarara!! SH Edit
Serial Kidnappings Arc Edit
After training, Mikage goes to get a drink from a vending machine and notices Mairu. The two speak about Yahiro and Kuon who were there earlier. Mairu suggests that Kuon maybe had some potential, to which Mikage doesn't give a solid reply about more focused on the other boy, Yahiro. She asks if Mairu noticed the boy's hands at all. Mairu replies she hadn't and asks why. Mikage asks her kouhai not to spread rumors, except with Kururi, or tell this to Yahiro's face. But she explain's that she caught a glimpse of Yahiro's hands and claims they were badly scarred saying it had many teeth marks on it. Mairu suggests that maybe a cat did the biting, but Mikage thought otherwise. She continued, saying that those teeth marks were from humans and that Yahiro must have repeatedly smashed his fists into someone's mouth. The teeth would scar up the skin and she said it could also get infected. She and Mairu wonder just how many teeth had Yahiro smashed before.
Eijirou Sharaku Edit
Main Article: Eijirou Sharaku
To be added.
Izaya Orihara Edit
Main Article: Izaya Orihara
As said earlier, it is heavily implied, if not outright stated that Mikage had developed romantic feelings towards Izaya during their days at Raijin Academy. These feelings went unrequited as Izaya simply treated her like another one of his "followers" (young girls like Saki Mikajima who he manipulated into obeying his every command) only paying attention to her when he needed her skills. The primary differences with Mikage was that she aided Izaya out of a genuine desire to get to know him while the others were more or less brainwashed into worshipping him.
In the present day, Mikage's exact feelings towards Izaya are left unclear for most of the story. It can be assumed she left some kind of impact on Izaya as she was one of the first people he asked for help when he decided to fight back against Yodogiri Jinnai, however Izaya assumes she is only helping him for an opportunity at revenge like most of the other members of Izaya's alliance.
Contrary to this belief, Mikage expresses to Kine that her feelings towards Izaya are much more complicated than what he assumes. While any romantic feelings have long since died out, Mikage still feels somewhat drawn to Izaya in some way, comparing him to that of an addictive drug. She knows staying involved with him will most likely be bad but at the same time, she can't bring herself to stay away completely. She even expresses respect towards the impartial nature of how Izaya manipulates others without discrimination, citing this as one of his few (if any) positive personality traits. As the series progresses, Mikage proves to be arguably one of the most loyal and capable members of Izaya's allies, as she and Kine are the only ones left at the end who didn't end up either betraying him or getting incapacitated somehow.
Mairu and Kururi Orihara Edit
Mikage's relationship with the Orihara Twins is significantly less complicated than what she has with their brother. Mikage considers them some of her best students and acts somewhat like a big sister to them. Likewise, the Twins have great respect towards Mikage, constantly getting excited when they get to see her fight for real.
Ran Izumii Edit
Main Article: Ran Izumii
Ran and Mikage appear to have a rather turbulent relationship. They appear to have some kind of history together as she appears to know him when they run into each other on the street. Mikage is comfortable working with Ran when the situation demands it but is quick to reprimand him should he step out of line. Ran, likewise, is slightly intimidated by Mikage but expresses a strong desire to beat her into submission, a challenge Mikage accepts.