Shinji has brown eyes and jaw-length blonde hair with a straight cut and many of his facial expressions reveal his upper teeth. While attempting to recruit Ichigo, he wears a standard Karakura school uniform, though he usually wears trousers, shirt and tie, often supplemented by a newsboy cap and long-coat. Shinji appears to have a round ring pierced in the middle of his tongue.
During his first stint as a captain, before he left the Soul Society, his hair was very long, reaching down to the lower part of his back. He wore the standard Shinigami robes with a standard, long-sleeved, captain's haori. Seventeen months after Aizen's defeat, Shinji returns to this attire with the addition of wearing his tie tucked under his robes. His hair which he kept in a short, straight-line cut after becoming a Visored has remained basically the same as well, with the exception of the bang now having a more asymmetrical cut with the left side being longer than the right.
Sometime before the Wandenreich's invasion of Soul Society, Shinji adds a further white robe between his haori and uniform, which is fastened at the front. His tie is also replaced by a broader cravat that is tucked under his new robe and is clasped using a small, silver slide.
Shinji is somewhat comical, adding a bit of levity to situations that are otherwise serious. He has a flippant attitude under normal circumstances and seems to like annoying his associate, Hiyori Sarugaki, which usually earns him a slap from one of her sandals. She, in turn, shows him absolutely no respect and frequently insults and attacks him; his behavior towards her is no better, frequently making faces or quick insults at her expense. He also has a history of referring to cute girls he meets as his 'first love', complete with a deadpan look on his face, despite the obvious lie (though he never did this with Hiyori, further annoying her). He also enjoys listening to jazz music, as he had a phonograph that played his vinyl records in his days as a captain.
Underneath this, though, he is quite perceptive in terms of regarding other people, and during his time as a captain, was one of the few people who appeared suspicious of his then-lieutenant Sōsuke Aizen, and could sense or see through some of his illusions. He also quickly notes parts of Urahara's personality. Aizen even admitted to being somewhat intimidated by him. Whenever angered or in combat, Shinji is fairly calm, serious, and level-headed.
Approximately 110 years ago, Shinji, in his capacity as the 5th Division captain, was preparing to attend Kisuke Urahara's promotion ceremony when he was interrupted by his lieutenant, Sōsuke Aizen. Shinji questioned Aizen's sense of fashion upon seeing that he was only wearing his standard Shinigami robes, prompting the two to start a debate of the necessity of wearing different clothes considering the event. When Aizen commented on the music Shinji was listening to, Shinji explained that it was jazz and it was all the rage in the World of the Living at the time. The two made their way to the First Division Headquarters to attend the promotion ceremony.
Upon the doors opening Shinji was ambushed by Lieutenant Hiyori Sarugaki of the 12th Division, though she was soon reprimanded by Captain Love Aikawa of the 7th Division. When Shinji finally gathered himself, he began to taunt Hiyori enraging her even further. As the group proceeded inside, Shinji asked Love what the head count was looking like for the ceremony, to which Love responded that almost everyone was already there. Shinji stated that he saw that no one from the 11th Division had shown up. Love explained that was the Eleventh Division's captain's way, as he did what he wanted. Shinji replied by saying just because he was the 10th 'Kenpachi', no one had the guts to keep him in check. He went on to say that he could not understand why they let such a loose cannon like him become captain. Love tried to ease him explaining that there was no use getting upset over it, as the chosen 'Kenpachi' had always held the position of the 11th Division captain, as it was a sort of legacy and it would not change any time soon.
Love went on to say that if Shinji wanted to complain about anything, then he should complain about the fact that the previous Kenpachi's ineptitude made it possible. The two captain's conversation was interrupted by the arrival of the 8th Division captain, Shunsui Kyōraku, his lieutenant, Lisa Yadōmaru, and 13th Division captain, Jūshirō Ukitake. Shunsui accused the two of gossiping behind other people's backs. Shinji then bore witness to the conversation between Shunsui and Ukitake about who had been captain the longest and what had happened to the previous 12th Division captain, Kirio Hikifune. He made note that they were going through captains quicker than toilet paper. Shinji was later seen waiting in line with the other captains as the newly appointed 12th Division Captain Kisuke Urahara arrived to the meeting. He was noticeably unimpressed at the demeanor and first impression Urahara made at his promotion ceremony.
Later the following night, he approached Urahara and told him why Hiyori was giving him problems: she had looked up at her previous captain as a mentor and a mother-figure. Shinji continued by giving him advice on how best to go about being a captain. He then remarked to Urahara that he could tell he wasn't the type who did what other people told him anyway, so it didn't matter what he said. Either way Shinji explained that he felt Urahara was the same kind of man as like him, so he should just meddle in his own business. While leaving Shinji asked, "How long do you plan on watching us from over there". Using his hand, Shinji revealed Aizen concealed behind some form of camouflage, Aizen complimented his captain and asked him when did he realize he was there, to which Shinji replied "When you were still in your momma's womb"; he then ordered Aizen to follow him. Aizen then commented on how scary a person Shinji was, to which Shinji replies that he was the scary one.
Nine years later, Shinji and Aizen were walking around the Seireitei when they came across Urahara, Hiyori, and 3rd Seat Mayuri Kurotsuchi. While Shinji once again engaged in a childish fight and argument with Hiyori, Aizen asked Urahara if he had heard the news to which Urahara tells him he hadn't. Shinji proceeded to take up the tale and told Urahara about the series of strange deaths that had taken place in Rukongai. Shinji also informed him that the 9th Division had been sent to handle the investigation.
With the arrival of the rest of the investigation squad, they pondered whether the creature was actually Kensei with Shinji stating that he didn't know if it was Kensei, but that if they didn't draw their swords they would be as good as dead. After Kensei let out a loud roar, Shinji picked up Hiyori and backed up, he then watched as Love proceeded to engage Kensei in battle. When Hiyori pleaded with them to stop fighting because it was Kensei, she began to cough. Shinji told her to be quiet as they had to stop him especially if it was Kensei. When a Hollowfied Mashiro Kuna appeared behind Rose and attacked him, Shinji called out to her so that her attention would be directed at him. Mashiro proceeded towards Shinji and attacked him, but he blocked her. He was assisted by the timely arrival of Hachi who used Bakudō #75. "Gochūtekkan" to subdue her. Hachi commented on how fast the others were in getting there. Hachi noticed Love having a hard time fighting a Hollowfied Kensei and used Bakudō #63. "Sajō Sabaku" to restrain him as well. He then asked Shinji what was going on and what had happened to Mashiro and Kensei, but they were interrupted by Kensei breaking free.
As Kensei proceeded to attack the others Hachi used Bakudō #99. "Kin" to finally bring Kensei down. Shinji commented to Hachi that he was impressed that he used a level 99 binding spell without the incantation. Shinji then asked Hachi if he could fix Kensei and Mashiro with Kidō, but Hachi plainly told him that he couldn't if he didn't know what the problem was. Suddenly, Hiyori began to cough uncontrollably, Shinji asked if she was alright and told Hachi to start with her first, but he was interrupted by Hiyori who began to choke out that she wanted him to let her go.
Hiyori then Hollowfied and attacked Shinji with a slash across his chest much to everyone's disbelief. It was then that a darkness falls around the rescue squad and they were attacked by an unseen assailant. Shinji was the only one conscious after this and upon the darkness lifting, he saw the assailant to be Kaname Tōsen, Muguruma's 5th seat. Shinji asked him how could he betray his captain, it was then that Shinji's attention was caught by the arrival of Aizen and Gin Ichimaru. Aizen explains that he had not betrayed anyone and that he was very faithful and he had just faithfully followed his orders.
Shinji admitted he wasn't as surprised as he let on and Aizen asked if he suspected him and stated that he had expected that much from his captain. Shinji then explained how he knew something was dangerous about Aizen, and that he couldn't be trusted. It was for those reasons that Shinji chose him to be his lieutenant: so that he could keep an eye on him. Aizen then told him that he was grateful, as due to his deep seated doubts he didn't suspect a thing. When Shinji stated that he already made it known that he had suspected him, Aizen elaborated stating that he didn't realize that the whole past month, it wasn't Aizen walking behind him. Aizen proceeded to explain the power of his Zanpakutō, Kyōka Suigetsu. Aizen informed Shinji that if he was as close to Aizen as other captains were to their lieutenants, then he would have been able to see through it by picking up on subtle differences between Aizen and the man acting as Aizen's double.
It was his lack of trust that kept them from getting close and as such, allowed Aizen to fool Shinji. He also explained that he could have always refused to be Shinji's lieutenant, but decided against that action because Shinji's suspicious nature made the position ideal to carry out his plans. Aizen thus laid the blame for Shinji and his comrades' current predicament at the feet of Shinji. Shinji was provoked by this statement and that triggered a speed-up in the Hollowfication process. Aizen thanked him for being so easily provoked and makes a note of the observed connection between the speed of Hollowfication and agitated emotions.
Shinji asked Aizen what Hollowfication is, but Aizen refused to speak on it any further. He then ordered Tōsen to finish them and after Hiyori was attacked, Shinji faced off against Tōsen. Shinji stated that he did not know what was going on, but he assumed that nothing had gone exactly as planned just yet. He then remembered that Aizen said agitation speeds up the process, so he resolved to remain calm and level-headed. He began to battle Tōsen beating the traitor back. Shinji continued to battle and soon gained the upper hand sending Tōsen crashing into the ground. But before Shinji could continue the fight, the Hollowfication process advanced further and incapacitated him.
Just as Aizen was about to finish off Shinji, Captain Kisuke Urahara and Kidō Captain Tessai Tsukabishi of the Kidō Corps, appeared and saved him from destruction. Aizen, Gin, and Tōsen made their escape and Tessai used Forbidden Kidō to preserve and transport the rescue squad to the 12th Division barracks. In his lab, Urahara tried to reverse the process using his created item, the Hōgyoku. Unfortunately, it ended up as a failure, not having the desired effect Urahara expected.
The next day, Urahara and Tessai were arrested under the orders of the Central 46. The Hollowfied Shinigami were sentenced to execution as Hollows. However, before any of their sentences could be executed, both were rescued by Yoruichi Shihōin, who brought them to a secret underground area. In the secluded area, she had also brought Shinji and the other Hollowfied Shinigami, along with the prototype for the new Gigai that Urahara was working on. With that epiphany, Urahara resolved to make ten Reiatsu-blocking Gigai to aid him, Tessai, and the eight victims escape to the Real World, where they hoped to find a way to undo the Hollowfication process.
Shinji appears floating upside down in the sky above Ichigo Kurosaki as he talks to Orihime Inoue and Yasutora Sado after he has dispatched a Hollow. Shinji disguises himself as a student at Ichigo's school and formally introduces himself the following morning to the class by writing his name backwards on the blackboard, saying that he is very good at doing things backwards. He then introduces himself to Ichigo and sits next to him, saying that they should get to know each other. Later that night when Ichigo goes off to fight another Hollow, he meets Zennosuke Kurumadani, the Shinigami sent to replace Rukia Kuchiki. Shinji approaches him from behind and proceeds to attack him, to which Ichigo blocks and notices that it is Shinji. He then asks if it is a Zanpakutō that he has and who he really is. Shinji tells him to be quiet as those with spiritual pressure like his can't afford to lose their composure otherwise they will be found out easily. Ichigo asks him to whom he is referring to which Shinji ask if he needs to tell him everything or if he is unable to find out on his own.
He then makes note of the arrival of some Hollow because Ichigo wasn't cautious of the level of his spiritual power, though Ichigo is more concerned with who Shinji really is. Frustrated with Ichigo's concern for the unimportant, Shinji dons a Hollow Mask and then asks Ichigo if he knows what it is, to which a greatly surprised Ichigo answers that it is a Hollow Mask. Shinji confirms that it is and also confirms that he has a Zanpakutō with a Hollow Mask. Shinji then explains that he is a Shinigami who has crossed into the realm of Hollows. He then plainly asks Ichigo to be friends with him as he is a Visored, the same as Ichigo. He then asks that Ichigo join them as he doesn't belong with the Shinigami.
Their conversation is interrupted by an unbelievably strong spiritual pressure from some unknown person that neither Shinji nor Ichigo can readily identify. Ichigo goes to find the owner of the spiritual pressure, much to Shinji's surprise; he asks Ichigo where he is going as they are not done talking yet. Ichigo tells him he refuses his offer and that he doesn't care who the Visored are, but he doesn't want to be part of it because he is a Shinigami and is definitely not one of them. After Ichigo leaves, Shinji's cell phone rings and he tells Hiyori Sarugaki that he has failed in his mission to recruit Ichigo, which prompts her to yell at him though he calmly tells her not to yell, as it is only a matter of time and they will wait.
The next morning, Shinji shows up at school and greets Ichigo as if nothing happened the previous night. When Orihime greets Shinji, he goes to give her a hug, causing a small altercation from some of her male classmates at what they perceive to be him making unwarranted advances. Ichigo grabs Shinji and pulls him outside so that they can talk. Ichigo yells at him for appearing at school after he said no to his attempt to recruit him. Shinji plainly tells him that he isn't going to give up after only two days, he tells Ichigo that he is very persistent and he will continue to bug him until he concedes. Shinji then explains that it is too late anyhow because once you're a Visored you're always a Visored, so whether Ichigo likes it or not, he is already one of them. He goes on further to state that all of his friends may be his friends now, but if he continues on as a Shinigami he will slowly be devoured by his inner Hollow until he loses his mind and his friendship would be "ground up into bits". Shinji then asks Ichigo if he has noticed that the Inner Hollow has begun to get stronger at an unimaginable rate. He tells Ichigo to come with him as he will help him keep his sanity.
While walking home, Shinji is attacked from behind by Hiyori. She then smacks him with her sandal and yells at him for not succeeding in his mission. The two are then interrupted by the arrival of Orihime and Chad, who were searching for Shinji. When Orihime asks who Shinji is and what he wants with Ichigo Kurosaki, Hiyori answers, stating that Orihime didn't think they would actually tell them. Hiyori introduces herself to them and they reply doing the same. Hiyori then voices her envy of their name's meanings compared to hers and Shinji's and the looks of Orihime compared to her own, even going as far as reaching for her sword and saying that she would just have to kill them as the conversation has become pointless. She is, however, quickly grabbed by Shinji who runs far away from Chad and Orihime with Hiyori over his shoulder. All the while she screams and argues with him, causing him to punish her in a very uncomfortable way. Hiyori eventually calms down and admits that she hates Humans and Shinigami. Shinji tells her that he already knows that that is why he was the one that went to enlist Ichigo and told her to wait.
When Ichigo decides to finally show up at the Visored's warehouse, Shinji admits he is surprised at how Ichigo could have found them considering how bad he is at sensing spiritual pressure; he then admits that they purposefully allowed their Reiatsu to leak to make it easy for him. Ichigo then tells him he has no intentions of joining them, he only came to "use" them to help him control his inner Hollow. Shinji asks him how he plans on doing that and Ichigo tells him by force as he leaves his body and proceeds to attack Shinji who counters his attack and the two begin to battle. Eventually, Hiyori attacks Shinji, knocking him away and through a nearby wall. Hiyori then tells Ichigo how this situation is really going to play out as she proceeds to battle him.
When Shinji witnesses Ichigo's inner Hollow nearly choking Hiyori to death, he, as well as the other Visored, quickly restrain Ichigo before he can kill her. Shinji then uses the tip of his Zanpakutō to break off what is left of Ichigo's Hollow Mask, stating that that example of Ichigo's power was sufficient enough. He then asks Hiyori if she has any complaints, though she is too terrified to answer. Shinji then tells Ichigo that one's inner Hollow is not something that one can subjugate with his mind, body, or a simple thought. But he assures Ichigo that since he passed the test, they will pound the "Hollow Suppression Technique" right into the core of his very soul. Shinji waits around with the other Visored as Ichigo does some training on an exercise machine, using Hiyori's training techniques on his own. He gets into a minor argument with Hiyori over boiling hot water. Ichigo becomes irritated with using the work out machine and throws it at Hiyori who blocks herself with Shinji.
Shinji then tells Ichigo that Hiyori's exercise machine is the basis of his future training as they decide the level of his future training will be determined by how long he can keep going while using it. He further explains that they will teach him how to govern his Hollow when he is able to use the machine for three days straight. Ichigo becomes irritated and yells at Shinji as he believes the Visored already know what he is capable of and that he doesn't need to use the machine as he can exceed its required use. He then goes on to say that all of this is pointless as he doesn't have the time to play and lay around. Shinji yells at him to shut up and then tells him that he has gotten quite big for someone who doesn't know how long the Hōgyoku takes to awaken. This surprises Ichigo as Shinji tells him that he knows nothing of the Hōgyoku or Hollowfication so he should stop his complaining. Ichigo asks him how he knows about all of that, to which Shinji explains he knows all about the Hōgyoku, the Arrancar, and Sōsuke Aizen and that he has known for many years. Shinji comes close to Ichigo and puts his hand up to his face and tells him that the story will have to wait for another time and states that he thinks it's time to let Ichigo's soul spend some time getting used to their methods, he then makes note that Ichigo has attained Shinigami powers, Shikai, and Bankai with incredible speed. Ichigo questions how Shinji knows all this, but Shinji simply says that Ichigo is right and speeding up teaching him Hollowfication might be better for him. Ichigo then passes out, and Shinji has Hachigen Ushōda erect a double dislocation barrier around the warehouse. He then tells an unconscious Ichigo that in a short while he will become a full Hollow, asking Ichigo not to get devoured by it and that he must consume him, remarking that if he is swallowed up in there, it is all over for him.
Shinji later goes with the other Visored down into his underground training area. Shinji then tells Hachi to put up a barrier down there too. Hachi is noticeably confused, to which Shinji quips don't act dumb as there is nothing cute about an old man saying "Ehhhh". Shinji also has him bind his legs and arms to which Hachi uses Bakudō #75.Gochūtekkan. He bears witness to Ichigo's transformation into a Hollow, warning the others that it has come. After Hachi erects a barrier around Ichigo and Lisa Yadōmaru goes in to fight him, Shinji tells her not to kill Ichigo and she responds that it's assuming that he doesn't kill her first. Shortly after her fight, Lisa asks Shinji how much break time they get, he mentions to her that since there are eight of them total in the rotation, ten minutes times 8 people would equal to eighty minutes. Though he is shortly corrected by Hiyori and corrects himself stating that it would be seventy minutes.
Eventually, Ichigo's Hollow form begins to rupture. Shinji looks on when Ichigo defeats his inner Hollow and gains control over his body. Shinji has Hachi bring down the barrier so that he may go and talk to him as Ichigo passes out. Shinji asks him how he is feeling to which Ichigo responds that he does not feel too bad. Later, while Ichigo is training, Hachi comments on how Ichigo hasn't really extended the duration as he can barely maintain his mask at all. Shinji tells him that it's not that simple. When Hachi becomes alerted when he detects someone has slipped inside his barrier, the other Visored are also taken by surprise. Orihime Inoue then shows up and is revealed to Hachi and the other Visored to be the culprit. They are shown to be quite shocked to see that a simple Human could perform such a feat. Shortly after Orihime leaves, the other Visored question who she is until Shinji tells them, causing Kensei to become mad that Shinji knows her. Shinji tells them that she is his first love. Lisa reminds him that he says that to all the cute girls and has even once said it about her. Later on, shortly after eating, Shinji asks Hiyori how the training is coming along to which she says it isn't going too well as Ichigo is nothing special.
Upon the arrival of the Espada in the World of the Living, Ichigo senses the presence of Grimmjow Jaegerjaquez and proceeds to rush off to fight him. He is held back by Kensei Muguruma and Love Aikawa, but Shinji tells them to let him go. Shinji later pursues him and saves both Ichigo and Rukia Kuchiki from Grimmjow's Cero attack after Grimmjow defeated both of them. He makes note that he hates getting involved in Shinigami fights, but concedes that when one hears the sound of fighting so close by one just can't ignore it. When Grimmjow asks him who he is Shinji tells him it doesn't matter and Grimmjow proceeds to attack him. Having a small discussion with Grimmjow, he is then suddenly attacked by the Espada, who declares his intentions of killing him. Dodging all of the attacks, Shinji realizes how violent Grimmjow is and the fight is destroying everything around them. Thus, Shinji dons his Hollow mask much to Grimmjow's shock as Shinji engages the Espada. Shinji tells Grimmjow that he is sorry, but he seems strong so he can't take it easy on him, as he prepares to fire a Cero at the Espada. The blast sends Grimmjow hurtling to the city below. Shinji then tells him that he knows the Espada minimized the damage of the Cero by hitting it with his own. An enraged Grimmjow pulls out his Zanpakutō and begins to release, but Ulquiorra Cifer comes and retrieves Grimmjow before he can do so.
Hueco Mundo arc
Mashiro Kuna brings in a package and Shinji is annoyed as he realizes Ichigo has left to Hueco Mundo, leaving the Visored with only a word: "Thanks".
Fake Karakura Town arc
Around the same time when Sōsuke Aizen, Gin Ichimaru, Kaname Tōsen and the top three Espada invade the Fake Karakura Town, Shinji reminisces about how Kisuke Urahara became a captain and how the Visored were subjected by Aizen's Hollowfication experiments. He then claims that they are in debt to Urahara and also have a score to settle with Aizen. Afterwards, Shinji and the rest of the Visored leave their compound, armed and ready for battle, simply saying: "Let's go."
Shinji and the rest of the Visored later arrive at the Fake Karakura Town, just when Aizen and his forces begin to gain the upper hand and confronts the latter with his usual grin. Shinji asks his fellow Visored if there is anyone in the Gotei 13 they would like to speak to and ends up in a short argument with Hiyori, followed by the rest of his team-mates expressing their disinterest in speaking to their former comrades (with the exception of Lisa, who flash steps away to see Captain Shunsui Kyōraku). Shinji then approaches Yamamoto to greet him, to which the Captain-Commander asks if he has come for revenge. Shinji plainly tells him that against Aizen, "Yes." As for the Gotei 13, he couldn't care less; if he was mad at the Gotei 13 it would be for "making the barrier around the Fake Karakura Town so hard to get through." He also points out that if he hadn't found Lieutenant Chōjirō Sasakibe outside the barrier, he and the Visored would still be outside. Yamamoto then asks Shinji if he is right to assume they are allies, to which Shinji tells him that it's too obvious they aren't. They are not on the Gotei 13's side, but they are against Aizen and they are Ichigo's allies. He returns to the other Visored, who ask him if he is done talking. He simply replies "No," but that now is not the time as the enemy is growing impatient. The Visored then proceed to bring forth their masks when Hooleer spews forth a huge amount of Gillian-class Menos from its mouth.
As the rest of the Visored engage in battle with the Menos Grande, Shinji confronts Aizen face to face and tells him that "it's time to finish this," as he partially removes his mask, he attacks Aizen. Unfortunately, his attack is blocked by Kaname Tōsen, who manages to make a small cut above his left eye. When he was about to receive another attack from Tōsen, Sajin Komamura steps into the battle, saying that he has decided to help the Visored and that "[he] won't accept a no as an answer".  While the Gotei 13 and the Visored are fighting the Espada, Shinji is engaged in a fight against Gin, which is abruptly stopped after Aizen attacks Harribel and calls Gin and Tōsen off.
Shinji appears near Hiyori and tells her and the others that it would be best not to be too quick to go near Aizen, explaining that with Aizen's ability one would be done for before it begins if they don't have a plan in mind. Hiyori tells him that they know that much, but Shinji tells her that he is specifically talking to her, as he tells her to stand down. Aizen begins to taunt them stating that regardless of what they do the ending will still be the same, as their fates had already been decided. Shinji tells Hiyori not to listen as he is only trying to provoke her. Aizen goes on stating they have nothing more to fear, seeing as they all died that night over 100 years ago. This taunt completely sends Hiyori over the edge, enraged she proceeds toward Aizen to attack him, as Shinji yells to her to stop. Before she reaches Aizen, Gin Ichimaru bifurcates her. Shinji screams to Hiyori and immediately catches the top half of her as she falls. Hiyori, now fatally injured, tells Shinji that she is sorry as she just couldn't control herself. Shinji calls to Hachi, but upon realizing that he only has one arm, he instantly remembers Orihime Inoue has healing abilities as he yells for Ichigo.
Shinji, while still holding Hiyori, stares down Aizen. Aizen comments that he likes the look in Shinji's eyes, as he looks like he has finally awakened after 100 years sleep. Aizen taunts him and tells him to face him, as he will unsheathe his sword especially for him. Shinji calls to Hachi, telling him that he is sorry as he knows he only has one arm, but he needs to take care of Hiyori or at least keep her safe until Ichigo returns. Aizen then asks why he would put his faith in that boy. Shinji simply tells him that he doesn't expect him to understand as he doesn't even trust his own followers. Aizen then explains that trusting someone means relying on them and only the weak do that, therefore it's not something that they need. Shinji questions how he can say that with all the followers he has, as he is sure that Aizen has asked them to trust him. Aizen corrects him stating that he is wrong as he never asked them to trust him at all. He told them to come with him, but he has never told them to trust him. In fact, Aizen has always told them not to trust anyone including him, though he sadly laments that there are not many strong enough to do that. Aizen further explains that everyone wants to find a god to believe in, and how he will become that god. Shinji comments on Aizen drawing his blade, being somewhat surprised that he would do so at all. He then asks Aizen if he is scared, but Aizen remains silent. Shinji then states that there is no point in ignoring him, as no matter how strong he is that he still has to be uneasy. He then quotes Aizen's own words from 100 years ago, about how Shinji had never opened up to him, never told him anything or even tried to get to know him. He then tells Aizen that because of that, he doesn't have a clue what kind of powers his Zanpakutō has. Shinji states to Aizen that if he thought that his Kyōka Suigetsu was the only Zanpakutō with the ability to absolutely control other people's senses, he was dead wrong. He then releases his Zanpakutō, Sakanade. 
The release of Shinji's Shikai prompts Aizen to comment that it's an interesting shape for a katana. Shinji responds that it is great, and he will not lend it to him. Aizen then states that he finds it strange that it does not give off any particular kind of aura, so he questions if he has heard wrong about it being able to control the five senses. Shinji tells him to take another look as it is already changing, as he casually asks if it has a nice scent. He then tells Aizen it is too late and welcomes him to the inverted world. Much to Aizen's surprise, he now appears as though he is standing upside down in mid air. Shinji explains that Aizen's senses have been inverted and moves to attack him while Aizen comments that the ability is interesting, as it causes everything to be opposite. Shinji is surprised when Aizen figures out that forward and backward are opposites as well as he turns around to block Shinji's attack, asking his former captain if he really thought that it would fool him. But Aizen is again surprised as his left arm is cut. Shinji explains that even his eyesight and where he gets cut is reversed as well. He then states that no matter how powerful he is or what Aizen tries, his body will always fight by reflex and fall to Sakanade's ability. Shinji goes to attack Aizen again, but misses, while Aizen states that he was trying to figure out what it was and now he sees it is nothing more than an optical illusion. Shinji then realizes he has been cut across his back as he passed by Aizen, which surprises him. Aizen then states that by controlling all five senses Shinji can't even begin to compare to his powers. He then notes once one gets used to it there is no problem as he taunts Shinji, telling him that it was mere child's play.
Shinji watches as Ichigo arrives back in the Human World via a Garganta and attacks Aizen. However, the attack is deflected by a powerful barrier. After some taunting by Aizen, Shinji, who has re-sealed his Zanpakutō, prepares to fight Aizen along with the other unoccupied Visored and Shinigami in order to avoid Ichigo becoming affected by Aizen's Shikai. Ichigo protests to everyone's decision to protect him, as they have already been wounded in previous battles and them fighting now would be overdoing it. Shinji argues that letting Ichigo fight Aizen alone is overdoing it and that everyone would be angry if Ichigo got killed because of fighting alone. He tells him that the battle belongs to every single one of them there. After Komamura moves to attack Aizen, Shinji asks Ichigo why he did not bring Orihime back with him, as she would be able to heal everyone to help fight Aizen. However, he notices that Ichigo did come back with Retsu Unohana and states that she was likely a better choice for a battle anyway. He then moves alongside Love, Rose, and Lisa to attack Aizen.
Aizen takes out Komamura, Rose, Love and Lisa, he then begins a fight with Suì-Fēng. Aizen moves to take out his Zanpakutō, but his sword and arm are immediately encased in ice, much to his surprise. Before he can react, Suì-Fēng stabs him in the chest with her Nigeki Kessatsu technique. Aizen notes that it is an interesting technique, but it cannot harm him. Aizen is then surprised as he is attacked from a shadow. Shunsui reveals himself having used his Kageoni technique, stating Aizen is careless as there is shadow on the ice. Hitsugaya tells Aizen it's over and rushes at him. Aizen notes to himself that Hitsugaya is so young, as he sees his chance and takes it without planning ahead. That is his biggest failing. Just then, he notices Shinji standing off to the side holding Sakanade's Shikai and smiling. Aizen then realizes too late that Hitsugaya is not attacking from the front, but the back as he is stabbed through the chest from behind. Much to their horror, however, Aizen reveals that at some point he switched places with Momo, tricking Hitsugaya into stabbing the innocent lieutenant. Furious at the deception, Shinji demands to know when Aizen cast the illusion, to which Aizen calmly states he has been using an illusion on them the entire time. As Hitsugaya attacks Aizen in a blind rage, Shinji and the other captain-level warriors are distracted trying to stop him. Aizen claims they're all wide open and proceeds to strike down Shinji, Suì-Fēng, Shunsui, and Hitsugaya. As they fall into the town below, Aizen states that he won't kill them and that they are to watch the outcome of this battle.
As the wounded are tended to, Unohana finishes her treatment on Hiyori. Lisa asks whether she will pull through and Unohana states that she will wake up as long as she doesn't give up on living. Unohana continues by stating it would be more appropriate to ask Shinji if she will give up or not. As Unohana walks away, Shinji tells her that he owes her one and the captain says she does not require thanks for saving the lives of her allies, to which Shinji remarks that they are not. After reflecting on what Hiyori would say at that point Shinji still retains that he owes her.
The Lost Substitute Shinigami arc
When Ichigo regains his powers, he notices that Shinji's power was used to help restore his own. When Ichigo goes to Soul Society to bring back the body of Kūgo Ginjō, Shinji, who is once again the Fifth Division's captain, questions if this is the right thing to do, asking if Ichigo can forgive Kūgo for what he did.
The Thousand-Year Blood War arc
Shinji attends a captain meeting where he is informed about Wandenreich's infiltration, and is ordered to prepare for war alongside other captains.
After the invasion of Soul Society begins, whilst relocating, he receives information from the 10th Division on the Sternritter's ability to steal Bankai, causing Shinji to wonder what exactly that idiot was doing. En route to the battlefield, he and Momo sense Yamamoto's Reiatsu moving onto the battlefield. When Momo remarks that she had never seen the Captain-Commander so angry, Shinji calls her an idiot. He says that while even he has never seen him like that either, they need to hurry, otherwise Yamamoto will take all the fun for himself. Shinji and the other captains are then later shocked to sense that Yamamoto had actually died at the hands of Yhwach. Shinji and the other members of the Gotei 13 are then further surprised to sense Ichigo Kurosaki finally enter Soul Society.
Once the Wandenreich retreat, Shinji is seen relatively uninjured as the Shinigami have their wounds treated by the 4th Division. There, he informs Ichigo that Rukia and Renji are out of surgery and brings him to the intensive care ward of the 4th Division barracks. He encourages Ichigo by reminding him that Yhwach had been forced to leave thanks to his intervention. Once Ichigo leaves, Rukia asks Shinji as to why he had such a sorrowful expression, to which he thinks Ichigo's putting it down to not being able to save anyone and doing so poorly in his fight. Rukia then tells him that there must be more to it. He then attends a gathering of the Gotei 13 as they mourn the loss of the Captain-Commander. He remains silent when some of the other captains break down and squabble among each other until Captain Kyōraku comes in to calm everyone down and remind them that the Gotei 13's purpose is to protect Soul Society.
As the captains await the arrival of the Royal Guard, Ichigo arrives. Shinji asks if Ichigo is there to watch the Royal Guard arrive, which he states he does not really recommend. As soon as the Royal Guards make their entrance, Shinji becomes disappointed as they were not what he had expected, but is then smacked on the head by a plump woman, who then asks if he and Hiyori are doing well. Not recognizing her, Shinji asks for her name and is shocked to learn that it is Kirio Hikifune, noting that she looks nothing like what she resembled before. Soon after, he watches as Suì-Fēng argues with the Royal Guards, as well as when Senjumaru Shutara reveals Byakuya, Rukia, Renji, and Ichigo's Tensa Zangetsu inside large orbs to take back to the Royal Palace along with Ichigo.
He gets into an argument with Hiyori on the phone over ordering some package before hanging up. Later, Shinji bears witness to the swift and complete invasion of Soul Society by the Wandenreich. When Urahara begins communication with all the captains, he states that he will introduce himself at a later point. Shinji says to himself that everyone already knows who he is. When Captain Sajin Komamura confronts the Sternritter "E" Bambietta Basterbine, Shinji also arrives to engage her and attempts to provoke her by using Sakanade to confuse and disorient her. He is surprised when she and the rest of the Sternritter all activate their Quincy: Vollständig. As Shinji wonders what the Vollständig is, Bambietta attacks him with an explosion. A badly injured Shinji is knocked to the ground as Bambietta unleashes even more explosions, however he is protected from them by Komamura.
Later, Shinji, having been healed by Hinamori, goes with her to the location of Marechiyo Ōmaeda and saves him from the advancing Soldat. Commending Ōmaeda for carrying both his unconscious sister and captain on his shoulder, he orders his lieutenant to heal the wounded. He talks to Ōmaeda regarding Kenpachi Zaraki's apparently imminent death and how he is their last hope. Saying they need to do everything to save Kenpachi, he is interrupted by Bazz-B who says he is going to stop them and then envelops the Shinigami in lava.
However, Shinji and Marechiyo manage to survive by using the power of Sakanade to redirect the attack, and later have their injuries healed by Momo before heading to the lab that Urahara has appropriated upon receiving an urgent summons. Soon afterward, Renji and Rukia arrive and express surprise upon seeing Shinji, who explains what happened. After entering the building and finding Urahara, Shinji asks him what is going on, prompting Urahara to relay the status of the various divisions. Noting that everyone is scattered, Shinji asks Urahara what he plans to do once all of them are here, and is shocked to learn that Urahara intends to break into the Soul King Palace.
Soon afterward, Shinji notices the display over the medical room shifting and informs Urahara that the operation is over. When Ukitake emerges from the medical room and proclaims that he has treated everyone, a shocked Shinji claims that Ukitake is the one who needs medical attention. After Kenpachi agrees to leave the search for his lieutenant to the rest of the 11th Division, Urahara gives Shinji a sphere to charge with his Reiatsu. Shortly afterward, Shinji is surprised by the arrival of the remaining Visored and briefly trades insults with Hiyori before claiming that she is also insulting Suì-Fēng, who promises to kill him if he is saying that they share a hairstyle.
With his comrades, Shinji arrives in Wahrwelt and they immediately make their way through the city in search of their goal. An unseen danger presents itself as Lille Barro soon begins attacking those that haven't kept up with the crowd.
Shinji becomes aware of the Shinigami being picked off and voices his frustration that they did not know where Lille was or where he was aiming, but they could not slow down either. Shunsui then decides to make himself a target in order to discover Lille's location, and Shinji yells at him for playing into the enemy's hands. As Shunsui confronts Lille, Shinji decides to leave him to do his own thing, although Momo wants to help Shunsui and asks Shinji why he is running. Shinji tells her that they are in a race against time and asks Nanao what they should do; she replies that she will go back to help while everyone else should go on ahead. Shinji asks her what Ukitake would say if he was still there, and knowing that Ukitake would say to leave Shunsui and go on, Shinji settles his argument and prepares to head off. Shinji says that Yamamoto would say the same thing, as it was the Captain-Commander's job to take responsibility for the lives of his soldiers.
Shinji and the remaining Shinigami reach the upper levels of the city, and he tells the others to stay focused. Suddenly, Shinji notices a figure flying toward them, and he and the Shinigami are displaced by its big landing. The figure turns out to be Gerard Valkyrie, who greets the Shinigami. Shinji tells Gerard that they didn't come to see him, but Gerard ignores him and says that they will have to defeat him to progress. Renji then attacks Gerard and Shinji prepares to leave the fight, but Gerard extends his cape to block his path and says that this was not going to be a one-on-one fight, but the Shinigami would need to overwhelm him all at once. Shinji expresses amusement at his statement.
Renji and Byakuya manage to push Gerard to the edge and Byakuya seemingly defeats the Quincy. Momo asks if Byakuya's excessive force was really needed, but Shinji tells her that Gerard seemed like he had a trump card up his sleeve. Shinji asks Byakuya to back him up, and Byakuya follows up by slamming Gerard into the ground with Senbonzakura. Before the Shinigami leave, however, a giant foot rises up and slams into the ground. A giant Gerard then rises up and shouts at the Shinigami, the force of his voice pushing them back. Gerard explains how his Schrift The Miracle works as he throws an obelisk at the Shinigami, splitting them up. Shinji grabs onto Momo to keep her from being blown away, but Gerard slams them into the ground with his hand.
Powers & Abilities
Master Swordsman: Shinji is implied to be a powerful combatant, being a Shinigami captain and the unofficial leader among the Visored. At one point, when Shinji begins to fight against Ichigo Kurosaki, the other Visored mention that Ichigo is foolish to battle Shinji, proven by the fact that Shinji is not taking the battle seriously (albeit Ichigo was also holding back, because he was trying to suppress his inner Hollow). Shinji is also able to hold off Mashiro Kuna during her Hollowfication without releasing his sword, though it took some effort. He was also able to fend off Kaname Tōsen while also trying to resist his Hollowfication. Shinji takes on the 6th Espada, maintaining his calm in the face of the destruction Grimmjow brought to the battle and pushing the Espada back with little effort, using only his Hollow mask and his swordsmanship skill.
Shunpo Expert: Shinji excels in Shunpo. His skill is great enough to easily outmaneuver Grimmjow, the sixth Espada. As a captain, even before he became a Visored, he was the first to arrive to save Hiyori, even when Lisa had a head-start and all the other captains left later at the same time. Shinji is also very quick at close-range. During his assault on Aizen, he is able to perceive and dodge Tōsen's sneak attack while sustaining only a small scratch above his left eye.
Immense Spiritual Power: As a captain, he has an enormous amount of spiritual pressure. Being a Visored, Shinji possesses a dual-type spiritual energy, part Shinigami and part Hollow. His spiritual pressure is said to be monstrous.
Keen Intellect: Despite his childish attitude at times, Shinji has shown himself to be a very insightful and perceptive man. During his initial tenure as captain of the 5th Division, he was able to see through Aizen's deceptions and some of his illusions. Aizen himself admitted to being intimidated by Shinji's cunning.
Sakanade (逆撫, Counter Stroke): In its sealed form, it resembles a normal katana. The hilt and sheath are red, and its guard is shaped like an hourglass.
Shikai: The release command is "Collapse" (倒れろ, taorero). In its Shikai state, the pommel becomes a large ring that allows Sakanade to rotate around Shinji's hand without him actually gripping any part of the Zanpakutō. This movement relates to his sword's special ability. The first few inches of the blade are covered by an extension of the cross-guard. Sakanade's blade is straight and slim, with the tip ending in a slanted razor-like edge instead of being tapered to a point. There are five holes along the sword's length.
Shikai Special Ability: Sakanade's Shikai ability creates a Sakasama no Sekai (逆様の世界, Inverted World). When spun, the sword creates a pink mist. Those who smell its pleasant aroma fall subject to an optical illusion. Shinji describes the release technique as something like a trump card. Up and down, left and right as well as forward and backward are reversed. However, it is not just the sense of direction that is changed; the opponent's eyesight, direction of incoming attacks, and injury locations are also inverted. Shinji claims that countering the damage from the inverted directions simply by processing it all within the mind is not possible. No matter how powerful the opponent, especially if one is accustomed to fighting, their body will not be able to adapt due to their reflexes preventing proper reaction, which causes them to continuously succumb to the power's effect. The effect of the Inverted World can be targeted at or neglected from specific opponents, making it ideal for use in group fighting. It also severely affects the equilibrium of those its power is used on giving them vertigo, causing confusion, disorientation and/or nausea. Shinji has further trained in its use to allow it to invert the words that he says as well.
Hollow Mask: Shinji's Hollow mask strongly resembles a pharaoh's mask, with a short, flowing hood hanging down the back of his neck. When donning his Hollow mask, Shinji's sclera turn completely black, and his irises become grey.
Power Augmentation: While wearing the mask, Shinji's Hollow powers supplement his Shinigami powers, giving him a vast increase in both strength and speed.
Cero: Shinji gathers energy that is displayed in a horizontal line at his fist. He then releases a crimson Cero with an extremely wide arc and devastating force. The Cero from a distance is powerful enough to cause grievous injury to an Espada of at least rank six, even at minimal power.
Enhanced Strength: While wearing his Hollow mask, Shinji has shown that he gains greater strength, which he uses to physically overwhelm Tōsen and Grimmjow.
Enhanced Speed: While wearing his Hollow mask, Shinji is able to move much faster, which he uses to overwhelm Tōsen and Grimmjow on separate occasions.
Enhanced Endurance: With his Hollow mask, Shinji becomes much more resilient to pain. He even states that when he first underwent Hollowfication that "wearing the mask feels like being in control of someone else's body".
Area Attacks: by attacking in all directions an opponet can bypass the disorientation effects caused by his ability.
Time Limit: Shinji can only maintain his hollow mask for 5 minutes at a time.
Appearances in Other Media
Shinji is a playable character known in the Bleach: Heat the Soul (series), Bleach: The 3rd Phantom, and Bleach: Versus Crusade. He uses his Visored mask in combat, which is quite powerful. He also appears in other Bleach games as an unlockable character. In Bleach: Heat the Soul 6, when Shinji performs a finishing move with Hiyori, she hits Shinji with her sandals, launching him into the opponent. In Bleach: Blade Battlers 2nd, after Shinji puts on his Hollow mask his EX-Attack changes into a pink, multi-directional Cero that bounces against a surface which lasts around 4 seconds. In Bleach: The 3rd Phantom, he is capable of using Cero without first using his Hollow mask, though, this is because his mask is not available as a transformation stage in the game. In Bleach: Dark Souls, he appears as a Spirit Card, but is not playable in the game.
An early drawing of Shinji can be seen in the art of the first chapter. This early design of Shinji ranked #103 with three votes in the second Bleach popularity poll.
The Viz version of Volume 44, VICE IT, mistakenly refers to Shinji's Shikai as his Bankai.
(To newly-appointed Captain Urahara Kisuke) "I hate to talk like I'm better'n you or whatever, but I'd like to just give you a little tip, as a guy who's had a little experience at this job. When ya find yourself in a position of command, even if ya sympathize with 'em, ya can't be too sensitive to your subordinates' feelings. You do things how you wanna do 'em. An' if doin' it your own way doesn't work out, then that just means the job ain't for you."
(To Misato Ochi) "Pretty good, huh? Doing things in reverse is my specialty."
(To Grimmjow Jaegerjaquez) "I swear. I really don't like gettin' involved in Shinigami fights. Oh well. When you hear the sound of fighting so close by you can't just ignore it."
(To Grimmjow Jaegerjaquez) "Can't ya hold back a little while you're fighting? If I dodge an attack and the city gets destroyed bit by bit instead, then I can't just ignore it and keep dodging."
(Before leaving to fight in the war) "I remember what Urahara said. 'I made no miscalculations. That was my greatest miscalculation of all.' And just like he predicted, the worst-case scenario came to pass. Man, we sure owe a lot to them. To Urahara, and also to Aizen, an' all. Let's go."
(To Genryūsai Shigekuni Yamamoto) "Can't say I've got much to settle with you. Although I do kinda wish you guys hadn't gone an' set up that crazy strong barrier before you started fightin'!"
(To Yamamoto, after being asked if the Visored were on the Shinigami's side) "Well, ain't the answer to that freakin' obvious? Not a chance. We ain't your allies or nothin'. We're just Aizen's enemies. Oh, an' we're also Ichigo's allies."
(To Sajin Komamura) "You sure 'bout that? Jumpin' in to help a bunch of total unknowns like us? Well, not that I'm quite sure what the heck you are either."
(To Sōsuke Aizen) "Up, down, left, right, back, front, the directions the damage is comin' from... do you really think you can wrap your head around fightin' with them all flipped around? Not a chance. Ain't no-one can do that. The stronger a guy is, the more used to battle he gets... the more naturally his body reacts to exactly what it sees!!"
↑ 1.01.11.2Bleach Official Character Book MASKED, page 200