In the story of Bleach, Captain Sosuke Aizen's mad scheme to become the king of Heaven was a threat to everything the heroes held dear, and Kisuke Urahara had a hand in it.

Kisuke never set out to be a monster like Aizen did, but he did undertake a secret research project that unintentionally laid the groundwork for Aizen's scheme, and was ridden with guilt ever since. Kisuke needed to make things right, thankfully, he had plenty of ideas on how.

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Kisuke Set The Stage For Aizen

Around 110 years ago, when Sosuke Aizen was a Lieutenant in Squad 5, the science-inclined Kisuke Urahara was conducting forbidden research. Hollows are beings to slay and purify as per Soul Reaper duties, but Kisuke sought to discover ways to understand and put their powers to use. He dove deep into the new field of Hollowfication, developing a small spherical artifact known as the Hogyoku. Its role was to break down the barrier between Soul Reapers and Hollows, unlocking new heights of power. Kisuke eventually grew disturbed by this project, and tried to abandon it. But Sosuke Aizen, who was thinking along similar lines (and had created a faulty Hogyoku of his own) decided to pick up where Kisuke had left off.

Kisuke tried to get out of the Hollowfication game, but the deed was done, and he had played his part in Aizen's scheme and the story as a whole. Aizen, using elaborate deceptions and his minions alike, experimented on nine Captains and Lieutenants and turned them into Visoreds by granting them Hollow masks. Kisuke was framed for this, and it was indeed partly his fault, since Aizen could not have gotten that far on his own. The Reaper scientist faced serious charges before the Council of 46, and Yoruichi helped him flee to Karakura Town in the human world. There, Kisuke's next role would be fulfilled decades later, when he ran across the Kurosaki family.

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Kisuke Created New Heroes

Kisuke eventually became allies of both Isshin and Ichigo Kurosaki. Aizen had released an experimental Hollow named White in Karakura Town one night, and it nearly killed a young Masaki, a human Quincy. Isshin Shiba of Squad 10 defeated White, but Masaki was dying from Hollow poisoning, so Kisuke helped Isshin give up his Soul Reaper powers to save this girl's life. In so doing, Kisuke saved Ichigo's life ahead of time, and finally began his path to atoning for his Hollowfication experiments. Kisuke's job was to clean up the mess he'd created, and ensuring Ichigo's birth was a fine first step.

Once Ichigo was born and grew up to 15 years of age, Kisuke was ready to take another step in fighting back against Aizen: by training Ichigo as a Soul Reaper. On the surface, he did it to help Ichigo gain the power necessary to rescue Rukia from Soul Society's criminal justice system, but this step had more far-reaching effects than that. Kisuke set the stage for Ichigo's remarkable progress, and the Hollow inside Ichigo granted him the power necessary to confront Aizen once and for all. Better yet, Kisuke was right there along Ichigo and Isshin to face Aizen, and together, the three of them defeated the rogue Captain and sealed him away with an advanced kido spell. Thus, Kisuke's role was complete, and he was as much of a hero as Ichigo was. He had created this whole mess, and he took responsibility for fixing it, too.

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