Hayato's Parents Edit
Kurogane's abnormal levels of intelligence and physical capabilities not only ostracized him from his peers during his younger years but also led to his parents fearing and abandoning him. Kurogane however had no qualms with this as he found living alone to be more efficient for his lifestyle.
Kurogane's former superior and mentor who taught Kurogane the significance of one's own beliefs. Kurogane became one of the youngest known Inquisitors to join the Dullahans and was placed under Kazuma, the then captain of the EXE. Both despised one another as Kurogane viewed Kazuma's work ethic as inefficient which had him frequently work alone and go against direct orders. Even if Kurogane's skill was unparalleled and his actions brought in results, Kazuma never acknowledged him as a proper Inquisitor who only functioned off the written law of the Inquisition. Their investigation of the group Insect Cage ended with the death of nearly all of its test subjects that Kazuma had wished to save while Kurogane was more concerned with documents that suggested the organization's collusion with the Inquisition. Kurogane blamed Kazuma for the deaths of the captured civilians and was ready to denounce Kazuma's wayward and arrogant thinking in favor of his own methods. Kazuma however showed no hesitation in the aftermath of the operation and upon seeing a single survivor in the rubble, deemed their efforts were not in vain.
Kurogane was intrigued with Kazuma's dedication and while it wasn't the first time he was lectured in the importance of one's "law", this was the first time he gave it serious thought. Kurogane decided to employ his superior's words for the first time and he became more cooperative and focused on using his peerless skills in service of others. Kurogane's prolific abilities soon became matched by his powerful mental fortitude and his most crucial assignment came from Sougetsu to investigate Kazuma's connection with the Inquisition's dissidents. Kurogane eagerly accepted this assignment to finally lock horns with Kazuma's apparent betrayal and confront him about the weakness of his law. Kazuma had no intention of resisting and only stated that he was handing over his rank of Captain to Kurogane and was quitting to spend time with his family. Kurogane was furious at how after all the times Kazuma preached about the proper way of the Inquisitor would turn his back like this and leave the other EXE members behind. While fully prepared to shoot, Kurogane found himself completely still and unable to do so, the inner beliefs that he held wouldn't allow him to. Kazuma walked away, pleased with Kurogane's change and assured him that Kurogane would become a fine leader. After his death, Kurogane's goals became clearer than ever by experiencing guilt over the lives he wasn't able to save. Years later, Kurogane gratefully acknowledged his captain's lessons but still held some sarcastic antagonism towards someone he never agreed with by personality.
Caligula and Maximilian Edit
Kurogane's Relic Eaters where his abilities allowed him to contract with two simultaneously, a feat that hasn't since been repeated. Kurogane's connection to Caligula is extremely straightforward as Caligula's requirements demanded vitality and Kurogane's overbearingly high amounts of it kept it constantly sated and obedient to his wishes. Caligula's effectiveness working in tandem with Kurogane's strength made it the one that was more used than the other as Maximilian's abilities were used for defense, something Kurogane rarely ever needed to rely on with his powerful stature.
Whereas Caligula had previous users, noted by their poor mental health, Maximilian's first master was Kurogane and the fact that it was seldom used made its personality formation occur in Kurogane's life-time. Maximilian's personality was shaped after Kurogane's own and shared his unbending belief in its own "law" which Kurogane found tiresome to deal with. It, like Caligula, shared a female persona but Kurogane pondered over why Maximilian's persona in particular was female when it was based off himself. Maximilian's requirements also seemed to be another reason Kurogane rarely ever used it as it demanded desperation and inferiority, the feeling of being caught under a critical situation, which was something Kurogane had never properly experienced. Kurogane's own understanding of his power stated that it would be his first and last time interacting with Maximilian again after he first utilized its true power.
The newly recruited EXE operative who took Ouka's position. Personally picked by Kurogane from the Banshees to be recruited into the Dullahans, Kanata acts as his direct subordinate in their operations. Kurogane no doubt has some degree of recognition of her skills but mostly finds issues with her mentality and work ethic as she is comparatively carefree. Kurogane however didn't seem to mind all that much of her relationship with the Inquisition's dissidents and was more concerned over the fact that she might ignore her duties as an Inquisitor and as his direct subordinate first.
Kazuma's adopted daughter who was the only one saved from the failed raid against Insect Cage. Kurogane had discovered her surrounded by the dead bodies of her adoptive family and opted to reassure her instead of chasing after the murderer in question. The two met again after Ouka's abilities led her to similarly become a part of the EXE at a very young age and Kurogane supervised her. Kurogane however found himself in a similar predicament that Kazuma went through with Kurogane's younger self: Ouka was exceptionally skilled for her age but was blinded by her hatred towards witches and acted alone. While Kurogane outwardly never showed it, he took particular care in making sure she didn't get into too much trouble as a means of honoring Kazuma's last wishes to protect his family. He nevertheless made it clear that she had to work her issues out.
The captain of the 35th Platoon contracted with Lapis. Kurogane didn't think too much of Takeru during their first encounter but wished him the best as Ouka's new captain. Understanding that Takeru has went through the burden of knowing Kiseki's affliction has him ever so slightly lenient towards him over issues regarding her. The two ultimately came to stand against each other where Kurogane found Takeru and his team's involvement in the war as misplaced and wanted them to hide in safety. Takeru's will to save everyone without compromises was just a pipe dream in Kurogane's mind and the fact that Takeru's contract with Mistelteinn was still active gave Kurogane the reason to conclude that Takeru should bow out from the fighting to avoid destroying the world. Kurogane admits his defeat however while Takeru is unconscious at Lapis' willingness to protect him convinced Kurogane that Takeru and his allies might just be able to change the outcomes after all. During the final moments of the war, Kurogane stepped in during Takeru's fight with Haunted to berate him over his priorities and stated that he will take upon Takeru's anger towards Haunted himself while Takeru dealt with the immediate threat of his sister.
Takeru's twin-sister and host of the Hyakki Yakou. Kurogane was responsible for pacifying her and capturing her prior to the beginning of the series. Even after the Hyakki Yakou claimed a multitude of lives that included a number of his comrades, Kurogane saw that Kiseki herself was under the mercy of her affliction. By his "law" he deemed that Kiseki herself was at no fault and considered her someone to be saved. Even then, Kurogane understood the extent of her abilities and sparing her was a tough feat alone as he fought with no intention of killing her. Kurogane held Sougetsu liable for her condition after her capture and threatened to judge him properly if he ever utilized her abilities for anything other than a deterrent for war. When Kiseki was handed over to the Alchemists, her cells weaponized, and Sougetsu brought her over to his side when she fully awakened, Kurogane saw fit to break away from the Inquisition and act alone to not only fight against Sougetsu but save Kiseki.
The sole surviving member of the 15th platoon whose immense regret and anger was compatible with a Relic Eater which led to being put under Kurogane's command. Kurogane's orderly attitude towards his duties conflicted with Kyouya's fervent aggression and the two quickly came to disagreements, with Kyouya being the one who first took an aggressive stance against his superior. Kurogane criticizes Kyouya's belligerence and simple-mindedness as shallow and is mildly humored at how fittingly Nero was paired with him. Kurogane relates Kyouya akin to a lost dog and didn't give too much thought into him other than being brash and childish. He however begins to see the formation of Kyouya's ideals when Kyouya goes out of his way to defend a shelter full of civilians and praises him over his growth.
Two of Kurogane's subordinates who were previously part of the previous generation's 35th Platoon with him before he became the president of the Student Council. Kurogane respects the two as cherished comrades but found Mamoru's overly nostalgic demeanor slightly distracting. Kurogane entrusted the captain's role to Mamoru as he left the Inquisition to pursue his own means of stopping the war. Mamoru and Iori's chase after him put him in the same spot Kazuma was with him leaving them behind to pursue his own ends. However, Kurogane didn't have the time to explain that his goal was to save as much people as possible and not get anyone else involved with his mission.
Kurogane's superior as the Chairman of the Inquisition. The two most commanding presences in the organization are wholly different from the other down to their clothing, with Kurogane being dressed in the darker colors of an EXE operative while Sougetsu wears an extremely contrasting all-white suit. Like every other character in the series, Kurogane is ultimately distrustful of Sougetsu and of his true intentions but nonetheless remained "loyal" to his will as per hierarchical order. Every step of the way Sougetsu had planned something that involved a large amount of casualties, Kurogane would offer an alternative plan to mitigate the damages, usually involving himself. Kurogane frequently remarks on his superior's wicked intentions but Sougetsu hardly ever takes offense to it. These remarks eventually had to Kurogane threatening to "judge" him if he ever overstepped his bounds, mostly regarding the usage of Kiseki's abilities. This event came to pass and prompted Kurogane's departure from the Inquisition and soon gaining his hatred after the deaths of Kurogane's former colleagues.
Kurogane's polar opposite who wishes only to revel in destruction and despair. The two vehemently despise one another as Kurogane finds someone who he cannot kill, even if he tries, irritating. Haunted on the other hand finds Kurogane's extreme strength and lack of emotions boring to deal with as it provides him no pleasure to kill him should he try to do so. Kurogane frequently interrupted Haunted during their encounters and in their final confrontation, Kurogane mentioned at how he has made it a hobby to interrupt him.