Sōichirō appeared to be an intelligent man with feminine features. He had bluish sliver jaw-length hair, yellow eyes and wears circular glasses. He wore a modified white coat and a black turtleneck shirt underneath with navy trousers, black boots, and a long bluish sliver scarf that reached his ankles.
At the pool, Sōichirō wore only his trademark scarf and tailor-made, tight white swim pants dotted with blue stars.
Eccentric and big-headed, Sōichirō’s real motives remained a mystery to everyone who knew him. After the loss of his parents, he developed a dangerous philosophy about humans and how they work. Although few could tell because of his bizarre persona.
He would often introduce himself with an odd title, usually to do with being the “patron Saint of children”. Cruelly, Sōichirō would treat Es like a doll, not caring for her individual self, only viewing her as a machine to be used and thrown away. When he found out that Tōya is a clone created from the Original Grymoire, although he hid it from him, no longer saw him as a living person and began to view him as nothing more than a “corpse”.
Although he never believed himself to be one, Sōichirō is also a hypocrite of his own beliefs. While he states everything he does is for the sake of humanity, he shows a lack of empathy for them, as he sacrificed and killed the Unions he was supposed to cure to harvest their crystals, forced Mei into working for using her father’s condition, guilted Tōya into helping him, showed no concern for Akira after removing his own crystal, and savagely beating Hinata for ruining his plans.
The director of Mitsurugi Agency New Yokohama’s seventh laboratory branch. Sōichirō was managing the Union’s protection and integrity. He was also the one who was giving direct instructions to Mei Amanohokosaka and Es. He seems to try hard to give off a cool and calm impression, but actually had a berserk side of him that he does not like to show. He admired anything cute and seems to have a say in Es’ choice of clothing. 
During his childhood, Sōichirō would often see his mother yell at his father whenever he returned home. It was around the age of fourteen, when he witnessed both of them die by her hands, which he laughed at for seeing how twisted the results were. This led to the beginning of his desire to control how the world works.
When he grew older, Sōichirō worked alongside several scientists, including Ryōko Kagari, on finalizing the T-system, which would allow them to control the fates and actions of people in order to benefit the world as a whole. However, Ryōko had changed her mind, believing that the people should decide their own fate instead of mindlessly following orders, and had stopped the experiment, which led to the Wadatsumi Mass Vanish Incident.
Sōichirō was one of the few survivors of the resulting accident, and was angry at the idea that he would need to start all over again. Upon discovering Tōya’s existence, he falsified information on the accident to make it look like his mother was the main culprit, in order to exact his revenge for her “intervention”.
Years later, he created Es to act as his personal agent. Around four years after this, he began work on a newer model – the Es-N units. At some point, he directly became Mei Amanohokosaka’s superior. While he was acting under the guise of helping the Unions he “rescued”, in reality, he was harvesting them of their Crystals so he could power the T-system, something that not even the Agency was aware of. He developed and used the Technology of Interest app to try and effect the choices of those within New Yokozaki City; effectively creating a miniature T-system.
XBlaze – Code: Embryo
Entering the Himezuru residence with Mei Amanohokosaka, Sōichirō introduced himself for the first time to Tōya Kagari and Hinata Himezuru. After getting rid of the former by requesting that she get him tea, he and Mei cornered Tōya and explained the existence of the Mitsurugi Agency and Unions. He then questioned the young man about the events that had expired earlier in the day, which pressed him to have Es watch the residence overnight while he ran a few tests. When they left, Mei told him that she had indeed felt traces of Blue, although faint.
The following day, he caught Tōya in the middle of asking questions to Es. Jumping in, he began to tell him about his amazing ability to hear Discover Calls from over 300 meters away. On top of this, he also began to explain that the Mitsurugi Agency had also bought Hakuō North Academy, and that he was to be its headteacher; furthermore, Sōichirō began to explain the event of the Wadatsumi Incident, and how Tōya was involved. He finished by telling the young man that it’s ultimately his choice about whether or not he wants to help them in the hunting of Unions, and bringing them in for 'treatment'.
Later that same day, he 'coincidentally' bumped into Tōya and Akira Kamewari, introducing himself to the latter. He simply arrived to congratulate the young man on accepting to help him and the Agency. Sōichirō left after thoroughly irritating Akira. A few days later, he ordered Es to keep a closer eye on Tōya since he had a feeling about the Original Grymoire. He had planted tickets to a swimming pool on Yuki Himezuru’s desk at her work.The day following his order, he turned up at the pool where everyone else was, shocking them with his rather odd attire. He ordered Es to have fun, and told Tōya that the Mitsurugi Agency also owned the private pool; because of Sōichirō, Mei was also present. He had several things to do, so his attention was stolen away from the lives within the Himezuru residence. Once these things had finished, Sōichirō called for Es to return to the agency.
A little later on, Sōichirō went to the Neo Yokozaki City University Hospital, hearing that Akira had survived having had his crystal ripped out, and was intrigued to see him and how he was recovering. Scaring off Kuon Glamred Stroheim, Sōichirō and Tōya had little time to talk as Sechs, Acht, and Drei, formerly of the Ten Sages, arrived. Sechs asked him what he desired most in the world, and Sōichirō replied that it was so the world could be safe, something that he tirelessly worked towards. After Sechs had asked Tōya the same question, the Sages left.
Some time later, Sōichirō began to put his plan in motion, and designated Tōya as an extremely dangerous Union, sending Es after him, and putting Mei in charge of a special unit sent to detain the young man; he didn’t suspect that the both of them would betray him. He organized someone to kidnap Hinata from her house, finally finding out that she was the Embryo all along.Seeing that both Es and Tōya had entered the interior of the lab complex, Sōichirō began to insanely insult Es, calling her broken. He then introduced the first of the Es-N to the both of them, and had it hunt them throughout the corridors. Finding that Tōya had scrambled down to his office, the scientist greeted him, being guarded by four more Es-N units. Sōichirō told him about his life and why he wanted to control the minds of the world, before revealing that the young man had fallen into his trap. Using the Es-N units, he had Tōya pinned down as they controlled his Original Grymoire. Reveling in the hopelessness of the teenager’s situation, he revealed Hinata was the Embryo, having inserted her into the T-system.
With the system complete, Sōichirō began to manically laugh until he was surprisingly stabbed by Sechs. Barely standing, he ordered the Es-N units to attack him, but they all fell in seconds. Sōichirō’s maniacal dream would never be realized as he was thrown into the Boundary.
- While not only being a part of the Takamagahara organization he also was the writer of the TOi program under the name TC which is also the name of one of the AIs in the Takamagahara system.