Izaya Orihara/Relationships

To be reworked.

Shizuo Heiwajima
Shizuo and Izaya have hated each other from the moment Shinra introduced them. During their very first meeting, Shizuo threw a punch at Izaya after being antagonized; which prompted Izaya to slash Shizuo with his knife. Further into their fight, Izaya arranged for Shizuo to be hit by a truck. Their fights have become legendary throughout Ikebukuro and have caused massive damage around the town.

The two of them are almost complete opposites of each other both physically and mentally. While Izaya is a calm and mostly collected individual who remains emotionally detached from most situations, Shizuo reacts impulsively on almost every single turn, causing him to go on a blind rampage. Where Izaya tends to use his superior agility and precise planning to get what he wants, Shizuo almost exclusively uses brute force to achieve his goals. The two are also different in their maturity. Shizuo is prone to random outbursts and sudden rages and has little self-control; however, he ultimately has a very mature goal to live a peaceful life and become strong enough to control himself. Unlike Shizuo, Izaya presents himself with a professional attitude when dealing with clients, and keeps his cool even while being tortured. In contrast to this, he is highly impulsive and does many unethical things just to see what will happen. In the Izaya-centric spin-off novels, Haruya Shiki describes him as a child with too much power.

While Shizuo frequently expresses a strong desire to murder Izaya in the most painful way possible, he is, ironically, the less aggressive of the two of them. Izaya hates Shizuo about as much as Shizuo hates him, although he is a lot better at controlling it out in the open. It is made clear that he doesn't even consider Shizuo human by his standards, considering him closer to that of an animal than anything else. As such, he gets extremely annoyed when Shizuo actually shows some sign of intelligence or maturity. It also seems that, between the two of them, Izaya appears to be the most fixated on their rivalry. This is shown in that Izaya frequently goes out of his way to antagonize Shizuo in some way, whether it be a simple prank or framing him for murder.

Toward the end of volume 12, Izaya reveals a bit more about why he seems so fixated on Shizuo. The first reason is that since he sees Shizuo as nothing more than a monster, Izaya feels extreme jealousy at Shizuo's ability to unwittingly attract others to him. This jealousy is further increased since Shizuo seems to try to isolate himself most of the time yet still manages to make new friends while Izaya remains shunned despite his attempts to connect with others in the only way he knows how. Izaya also holds the belief that only humans possess the ability to slay monsters. Following this line of thinking, Izaya believes that if he manages to defeat, or even kill Shizuo, he thinks it might make him feel more human.

In Izaya's novel, a few years have passed since their last fight. Izaya suffers from trauma and fears Shizuo, but accepts his loss towards him and decides not to come back to Ikebukuro, even though his conflict might be the same or worse than before. In the introduced chapters of the novel, Shizuo is interviewed about Izaya, though Shizuo just asks the interviewer to tell Izaya never to return to Ikebukuro.

In Durarara!! SH, Celty and Shizuo look at the building that he and Izaya destroyed during their final fight. Shizuo wonders what would have happened if he and Izaya had not been enemies. However, Celty replies that too would not have been good, as Izaya would simply have used Shizuo as another pawn.

Shinra Kishitani
Their friendship can best be described as "bizarre." Izaya encounters Shinra on the opening day of Raijin Middle School, when Shinra—his classmate—approaches him with an invitation to found a Biology Club together. His reasoning that Izaya's interest in "human observation" falls under a biological bailiwick is met with rejection, but Izaya eventually becomes intrigued with Shinra as a person and starts asking around; through talking with other students, Izaya realizes Shinra has no interest in humans whatsoever, unlike himself. His curiosity as to why leads him to finally agree to become the club's Vice President.

The Biology club is essentially a front: for Shinra, it is an excuse to make a friend (thereby earning the approval of his 'beloved'); for Izaya, it is a means to facilitate baseball gambling with his peers. This gambling ring, which Shinra tries to dissuade Izaya from upon learning it exists, leads to a turning point in their relationship. Nakura, a fellow student who lost his father's money to gambling, will barge into their club room with a knife in a desperate move to reclaim his monetary losses. Shinra darts between the knife and Izaya and is consequently stabbed in the stomach, much to Nakura's horror. Izaya takes the blame for the incident and uses it to continuously blackmail Nakura throughout the following years.

Izaya has cited the incident as one of many that influenced his personality; he had envied the way Shinra seemed to observe humans from a "different plane." Izaya would once again join Shinra as a classmate at Raijin High School, where Shinra personally introduces Izaya to his elementary school friend Shizuo Heiwajima. So begins Izaya and Shizuo's mortal rivalry. Izaya attends Raira University after graduation and Shinra does not, though Shinra occasionally spends time with him on campus.

Currently, Izaya believes he is not an important friend in Shinra's life since Shinra's world revolves around Celty Sturluson. A telling example is seen during Shinra and Celty's date away from Tokyo; when Izaya calls Shinra from the hospital—the latest in a long line of callers interrupting the couple's date—Shinra swiftly hangs up. Later, Izaya returns the favor by giving Shinra the cold shoulder during Shinra's convalescence.

Nevertheless, multiple instances in the novels reinforce that Shinra is the only person whom Izaya actually considers a friend rather than merely another beloved 'human'. Though Izaya did not visit Shinra when Shinra was recovering from his assault, Izaya does have his people capture Kisuke Adabashi—Shinra's attacker—and keep Adabashi confined at his apartment until the man eventually escapes. Likewise, Shinra does at least see Izaya as one of his only friends and will often defend him in front of Celty and Shizuo—even as he admits "there's not a single ounce of goodness in him."

Shinra is Izaya's opposite. While Izaya claims to "love all humans," Shinra has no interest in or feelings toward other humans at all; he is instead devoted to a non-human, and Izaya holds no love for non-humans. Despite Shinra's lack of interest in humans, Izaya considers Shinra's assessment of humanity to be accurate. Not only was Shinra the first person to see through Izaya's nature, he remained and continues to be on friendly terms with him—unlike others who have expressed disgust upon better comprehending Izaya as a person. Granted, Shinra's objectivity when it comes to all humans, whether they are 'good' or 'bad', makes assessing what he truly feels regarding 'friendship' difficult. Moreover, Izaya claims to see all humans equally, whether they be kith or kin or something else.

Although there has been no contact between them since Izaya vanished from Ikebukuro, they both still regard each other as "friends." Byakuyamaru Natsugawara, who happens to be acquainted with the Kishitanis, has urged Izaya to pay Shinra a visit in the ending of A Standing Ovation with Izaya Orihara, to which Izaya has replied, "I'll see about that, if I have the time." Kazane Kinomiya, Shinra's maternal half-sister who has had past dealings with Izaya, likewise desires Izaya and Shinra reunite.

Mikado Ryuugamine
Izaya and Mikado meet on the internet; Mikado does not know that Kanra is actually Izaya for a long while. Mikado meets Izaya in person on Mikado's second day in Ikebukuro. Izaya knows that Mikado is the leader of the Dollars, but promises not to sell the information to anyone. He doesn't keep this promise exactly; instead of selling the information, he gives it away to Masaomi Kida for free. In the manga, Izaya tells Mikado that it wasn't a coincidence that he met him - he was looking for him.

Later in the novels, Mikado begins to rely on Izaya's information and advice. This is similar to how Masaomi depends on Izaya to lead the Yellow Scarves (which eventually led to his downfall). Vol. 7 foreshadows that Mikado will be led down a dark path because of Izaya. However, in the same novel, Aoba reveals that both he and Izaya have grossly underestimated Mikado.

Mairu and Kururi Orihara
Kururi and Mairu are Izaya's younger twin sisters. They grew up in the same house as Izaya, where all three siblings were said to have had "fairly normal parents." Izaya believes that their eccentricities developed because of his influence on them: he told them as children that they were copies of each other and therefore had no real purpose. When they were younger, he often had to take care of them because their parents were almost always working abroad. Izaya states that aside from Shizuo, they are the only humans that he doesn't know how to deal with, which may explain why he's annoyed by them. While Mairu and Kururi are inseparable, their feelings on Izaya are not as clear—on the one hand they say that they still consider him family, but on the other they wouldn't mind killing him and throwing his dead body in the garbage in order to meet their idol: "Hanejima Yuuhei," Shizuo's younger brother. However, in the twin's episode of Epitome of Eighteen Histories, the twins claim that they "couldn't care less" but they still "sometimes" love him.

Izaya displays some affection for his sisters when he sends Celty to stop some thugs picking on Kururi; he claims that he only did this because he needed a distraction for a job. However, he also sends Eijirou after some other thugs who were targeting Mairu when it was not work-related.

Namie Yagiri
Izaya and Namie have a complex relationship. Although Namie approaches Izaya in order to prevent her own arrest, she despises Izaya. Namie is the only person Izaya has no problems sharing his plans with despite Namie's indifference towards him. Regardless of their feelings toward each other, both Izaya and Namie seem to have grudgingly accepted the other as the closest they'll get to normal human interaction.

Saki Mikajima
Izaya was like a guardian to Saki and took care of her before she left with Kida. Saki looks up to Izaya as an admirable person to the point that she is mesmerized by him. He uses this to his advantage; even instructing her to get kidnapped (which results with her legs being broken). However he still visits her in the hospital, where he ordered her to stay for a year. Despite his twisted and manipulative ways, he does have a form of attachment towards her as he appears to be genuinely sad when she leaves him and runs off with Kida, since she is one of the few characters that actually likes Izaya. Saki's attachment towards him is still there as she is grateful to him for bringing her and Kida together.

Celty Sturluson
Due to her job as a underground transporter, Izaya is in charge of giving Celty her missions. However, Celty doesn't like Izaya in general due to the manipulative tactics he uses. She always suspects him of being involved with many of the major events that happen in the city and doesn't trust him at all. In turn, Izaya considers Celty to be one of many pawns at his disposal. After obtaining Celty's head, Izaya tries to start a gang war to see if it will awaken Celty's head. Despite his actions, Celty helps save Izaya's life after he is seriously injured during his fight with Shizuo.

Masaomi Kida
Izaya has manipulated Masaomi from the very first day they met. He manipulated the Blue Squares to attack the Yellow Scarves and vise versa. He then abandoned Masaomi when Saki was kidnapped. Masaomi has hated him ever since.

Shinichi Tsukumoya
Shinichi Tsukumoya is an undesired and disliked source of information for Izaya. However, Shinichi always has a leg up regarding information and is a very necessary contact for Izaya to have. Shinichi first made contact while Izaya was still a high school student--- by mocking him for a video game Izaya himself had made. Their cooperation afterwards takes place wholly in Shinichi's private chatroom, and is almost always hostile. Shinichi is one of few people able to shake Izaya's 'mask' and invoke actual irritation from him. Izaya intends to get back at Shinichi for all the years of insult and mockery if he finds out where Shinichi lives (unaware he might actually be a living AI and not have a physical form at all).

Izaya once used Shinichi's name as an alias to annoy him and Shinichi responded by posting a forged photo of Izaya crossdressing on the internet and entering it in a contest.

Haruto
Haruto is one of the children Izaya took in after orchestrating the deaths of Haruto and Himari's fathers. Haruto appears to idolize Izaya, doing whatever he says and thinking very highly of him. He even went far as to say he wanted to become just like Izaya, something Izaya objected to. Izaya has included Haruto and Himari in his plots but does not seem to treat either child badly.

Himari
Himari is one of the children Izaya took in after orchestrating the deaths of hers and Haruto's fathers. Unlike Haruto, Himari detests Izaya, believing he has ruined her and Haruto's lives. She does carry out the orders she is given, however and seems to want to become like Izaya after finding out he can be defeated.