Souji Hiura

Souji Hiura (氷浦蒼士, Hiura Sōji), (written as Soji Hiura in the Viz Manga), is sent to Karasumori under orders to assist the Kekkaishi, but turns out to be little more than a puppet who obeys his current master for the time being. Yoshimori distrusts Souji on sight, recognizing him as a previous enemy, but eventually grows fond of him and is saddened by his blank, almost child-like state. But even as they grow closer, Souji's mysterious past, as well as the orders of the person who sent him to Karasumori, repeatedly cause his motives and trustworthiness to be called into question.

Appearance
Souji has spiky blue hair and often wears a dark cloak. His most notable feature, though, are his eyes, which Yoshimori originally compared to that of a dead man. He was raised to have little emotion, and thus has a permanent neutral expression, though he will frown when truly upset.

Personality
Souji appears to be the foremost example of the Commander's Puppet Soldiers program: at most times, he displays little or no emotion, yet excels in battle to an almost frightening degree, sometimes to the point of ruthlessness when unnecessary. Although his movements during battles are exceptionally fast, Souji seems to be slow to thought and speech.

Most of Souji's behavior is governed by standing orders from the Commander, who he views as his ultimate authority figure. Souji essentially exists to obey: he will carry out any order, without hesitation, from a recognized authority figure, provided it does not conflict with the Commander's directives. In a rather extreme example of this, Souji thought nothing of taking his own life after Yoshimori halfheartedly suggested it, and stopped only because it would prevent him from carrying out orders.

After some exposure to Tokine and especially Yoshimori, Souji's relationship with them becomes more solid, despite obvious trust issues. He especially takes any promise he makes to Yoshimori seriously, and seems to truly regret any time that he is unable to keep them. According to Yoshimori, Souji does not seem to know how to lie. He also seems to be interested in things such as mechanical pencils and certain kanji. Because Souji doesn't have many things that belong to him, he tries to take excellent care of whatever he owns.

An apparently unintended consequence of Souji's reprogramming is his tendency to become emotionally attached to some (but not all) of his recognized authority figures. Souji's ultimate loyalty was to the Commander, who he viewed as his highest authority, and to Suigetsu, who always treated him kindly. He also has a great deal of admiration for Number 1, to the point where being ordered to face him in battle nearly moved Souji to tears. Souji's time at Karasumori resulted in Yoshimori becoming an authority figure of great importance.

History
Souji was originally known as Number Three (三号, Sangō), one of the Commander's nameless puppet soldiers, created to be perfect fighters with no emotions to hinder them. His newer name was given to him by Suigetsu, who also showed him how to write it. Much of Souji's past is shrouded in mystery, because he has very few memories, and even those are safeguarded by directives from the Commander, which prevents Souji from sharing most information about himself or his orders. However, it is clear that he was a member of the Shinyuuchi Hunters for some time.

The Masked Hunter
Souji first appears in Hidagou as Yoshimori is investigating the crumbling dimension, wearing a hat and scarf that cover his face with the exception of his eyes. He sees the tenketsu-like object Yoshimori had found and tries to retrieve it, which leads Yoshimori to determine that he played a large part in the Shinyuuchi hunting. After overpowering Yoshimori and retrieving the object, Hiura flees only to later appear unmasked at Karasumori, claiming to have been ordered to protect it and obey the orders of the Kekkaishi. Instantly Yoshimori recognizes him based on his eyes and is very suspicious of him, and declares that Souji will stay at his house after learning that he has a letter asking the Yukimura family to stay with them. Paranoia causes Yoshimori to place a Kekkai around Souji at night so he may not sneak out and attack anyone, though this is both unnecessary (as he'd ordered Souji not to leave, and Souji seems incapable of disobeying orders) and useless (Souji proved he could easily cut though Yoshimori's Kekkai when they met in Hidagou). The next day Yoshimori and Tokine are surprised that he does not plan to attend school, and he spends the day helping Shuji Sumimura clean up the house.

Assisting the Kekkaishi
Souji assists the Kekkaishi with their duties and Yoshimori takes him to the forest to talk, where he realizes that Souji was brought up to be rather simple-minded after Souji inquires if he himself is human due to Yoshimori's comment about him being strange. Sen follows him one night to a secret rendezvous with a suspicious conversation, and remains suspicious of him and tries to convince others, but his attempts are ignored. Yoshimori decides to trust Souji and makes him promise not to let anyone around them get hurt, even himself. Yoshimori gives him a mechanical pencil he's interested in, and he seems to treasure it greatly. When Souji is absent on the same night as Okuni's death, the mechanical pencil is found there by her underlings and is connected to Yoshimori. In turn, he makes Souji promise that if he feels like killing anyone else again, he will first come and try to kill Yoshimori so that he may stop him.

During the attack on Karasumori, Souji fights No. 1 and No. 2, and in the process saves Sen from One. Sen realizes that Souji's injuries are worse than he's showing, keeping them secret so that he won't have to break his promise to Yoshimori about not getting hurt. He is about to defeat Two when he remembers that promise to Yoshimori and hesitates, giving One the opportunity to rescue Two. Later when Shichirou Ougi arrives, he accidentally attacks Souji thinking he's One, putting him in critical condition. When Souji eventually woke up, he was devastated over breaking his promise to Yoshimori not to get hurt, though he's reassured. Kei Sazanami is then revealed to have arrived with plans to interrogate Souji, and a look into his memories revealed Suigetsu and a block placed by another psychic to prevent others from gaining too much information from his memories.

To celebrate Souji waking up, Yoshimori bakes a giant cake for him. After Souji decides he likes "brown cake" (chocolate) better, Yoshimori makes one for him, only to discover Souji missing from his bed. Souji is later seen with No. 0 at another Shinyuuchi hunting and various other times in the company of the Commander. Zero states in a conversation with One that it seems as if Souji is doing some "soul searching", as he seems to zone out a lot and look into space.

Equipment
Earpiece: Souji formerly wore an earpiece on his left ear at nearly all times. This appears to be unique to those who were part of the Commander's puppet soldier program. At least in Souji's case, his earpiece appears to transmit signals, which in turn leads him to meeting points with others under the Commander's sway. This allowed him to receive updates and new orders without actually speaking to the Commander directly. He no longer wears the earpiece after the events at Hakuma.

Powers & Abilities
Puppet Soldier Training: Souji was trained as one of the Sousui's puppet soldiers. As a result, while he has precious few memories and emotions, his body and powers have been trained to the maximum level, and he is a near-perfect fighting machine while in combat.
 * Blade Materialization: Souji's primary weapons are large, glowing blades that he can materialize from seemingly any area on his arms and legs. He can increase the length, size, and number of the blades at will. Souji can also use the same aura that shapes his blades as a defensive barrier to lessen damage, and to increase the agility in his limbs.
 * Ayakashi Majiri-Level Body: Members of the Night Troop observe that Souji's body displays levels of agility, strength, and endurance that only an Ayakashi Majiri should be capable of. However, they can sense no aura from him that would indicate that he is one, nor does he begin to transform as other Ayakashi Majiri do when exposed to a great deal of Karasumori's power.

Allies
Though he first encounters Yoshimori as an enemy, Souji is then ordered to assist Karasumori's Kekkaishi. Naturally, Yoshimori is extremely suspicious of his true intentions, but gradually learns that Souji is virtually a blank slate, basically only capable of obeying orders from whoever his current master is. Yoshimori takes it upon himself to try and reform Souji into a normal person, with some success: Souji places great value in Yoshimori's opinion of him, and reacts with grave sorrow if he ever feels he has disappointed Yoshimori in some way. Likewise, Yoshimori comes to consider Souji a friend and trusted comrade.

Trivia

 * In the name Hiura Sōji (氷浦蒼士), 'Hi' (氷) means ice, 'Ura' (浦) means riverside, beach, and shore. 'Sō' (蒼) means blue, and 'Ji' (士) means samurai or warrior.