Sousuke Aizen

Character outline

Aizen served in the Fifth Division, eventually rising to lieutenant under Captain Shinji Hirako. He attracted followers like Gin Ichimaru and Kaname Tōsen. After Kisuke Urahara created the Hōgyoku, an item thought to fuse Soul Reapers and Hollows, Aizen conducted experiments on the Soul Reapers who later became the Vizards. Shinji was among his subjects; he became aware of Aizen but realized too late that Aizen had used his distrust against him.

Aizen also framed Kisuke for creating the Vizards, forcing him into exile, and discovered the Hōgyoku actually fulfills its user’s wishes if they possess the will to see them through. Aizen recognized potential in Shuhei Hisagi, Momo Hinamori, Izuru Kira, and Renji Abarai, bringing the last three into his division. He continued his hybrid experiments with his creations Metastacia and White, affecting Rukia Kuchiki, Isshin Shiba, and Masaki Kurosaki.

After leaving the Soul Society, Aizen, Ichimaru, and Tōsen went to Hueco Mundo and sought an alliance with its self-proclaimed god king, Barragan Luisenbarn. When Barragan refused, Aizen revealed all the Hollow minions had been killed during their talk and forced Barragan into submission. He then took over Barragan’s palace, Las Noches, rebuilt it to his liking, and recruited Tier Halibel and other Arrancars to serve as his Espadas. Aizen is exceptionally powerful and intelligent, surpassing many captain-level Soul Reapers.

Before activating the Hōgyoku, he noted that even half-awakened, it could be fully activated temporarily by fusing with someone possessing at least double the spiritual pressure of an average captain—referring to himself. After embedding the Hōgyoku in his body, he underwent several transformations that vastly increased his strength and power.

Appearances

Aizen orchestrated the entire chain of events from behind the scenes. He first engineered the meeting between Rukia Kuchiki and Ichigo Kurosaki, which led to Ichigo becoming a Soul Reaper. To locate the Hōgyoku hidden inside Rukia, Aizen sent Hollows to Karakura Town, drawing the attention of the Soul Society. He then murdered the members of Central 46 and used his Zanpakutō to create an illusion of them, manipulating them into sentencing Rukia to death. This set off a conspiracy among the Thirteen Court Squad captains. Gin Ichimaru faked Aizen's death, causing the captains and lieutenants to turn on each other, but Captain Retsu Unohana discovered the truth. Aizen removed the Hōgyoku from Rukia and fled to Hueco Mundo with Gin and Kaname Tōsen.

In Hueco Mundo, Aizen planned to use the Hōgyoku to sacrifice the souls of Karakura Town, creating an Ōken to kill the Soul King. He strengthened his Arrancar army with the Hōgyoku and sent some Espadas to the human world to gather information on Ichigo. Claiming he needed Orihime Inoue's power to restore the deteriorating Hōgyoku, Aizen had her brought to Las Noches. This kidnapping was actually a distraction for Ichigo, and by sacrificing the weakest Espadas, Aizen aimed to cut the Soul Society's forces in half before his attack on Karakura Town. He arrived with three of his strongest Espadas, but after Staark and Baraggan were defeated, Aizen decided he had surpassed his own minions. He struck down Halibel and took on the opposition himself.

When Ichigo confronted him, Aizen revealed that he was the only person unaffected by his Zanpakutō's power. Aizen disclosed his role in shaping Ichigo's life and struggles since meeting Rukia, and nearly revealed Ichigo's lineage before Isshin Kurosaki intervened. Aizen then explained that he had absorbed the Hōgyoku, which granted his desire for a Hollow-like form, allowing him to easily defeat his enemies.

Reception

Charles White of IGN found the story's twist and the truth about Aizen both fascinating and interesting, though he took issue with the Zanpakuto's power, calling it far-fetched and overpowered. He also felt Aizen lacked any flaws and that his betrayal was so meticulously planned it strained believability. However, White praised the shift in tone when Aizen was revealed as a villain, commending the animators for making his face seem evil without altering the animation itself.

He noted that the Aizen viewers first knew as the nicest guy now appeared as the most evil jerk imaginable. Carl Kimlinger of Anime News Network described Aizen's antagonist reveal as brutally unpredictable, finding the accompanying violence frustrating yet satisfying, and he lauded the abundance of revelations. Kimlinger highlighted Aizen's impressive development as a villain, wishing all villain grandstandings were as thrilling. Theron Martin, also from Anime News Network, credited the scene as one of anime's biggest "I am a total bastard" moments.

Bryce Coulter of Mania Entertainment observed that the episode makes viewers want to hate Aizen, given how he manipulated characters' actions and easily overpowered most of them. Aizen's English voice actor, Kyle Hebert, characterized him as a mysterious, calm, and cool figure, evoking a sense of wondering where this guy comes from.