In the underground laboratory of Las Noches, Higashi Shuuichi stood motionless, his gaze fixed on the ground.
Nervous?
Not at all.
From the moment over eighty years ago when he decided to pledge loyalty to Aizen—carefully feigning weakness to bait and eventually win the man's favor, securing a place among his original conspirators—Shuuichi had always known this day would come: a day when he'd have to turn against his fellow Shinigami.
He felt no guilt. In his eyes, those people were doomed the moment Aizen marked them. If they didn't die by his hand, they'd fall to Aizen, Tōsen Kaname, or Gin Ichimaru eventually. The only difference would be how much effort Aizen would have to expend to kill them.
And saving them? Shuuichi never entertained such naïve ideals. He wasn't some chosen one sent by the gods to change the world. He was just a man with knowledge of the future, struggling to stay alive in a world that wasn't his. He had no responsibility to be a hero.
So when Aizen gave him his latest mission, Shuuichi found himself strangely relieved.
Was he excited? Not really. If given a choice, he would have preferred to continue living as the 4th Division's Vice-Captain, occasionally sneaking spirit particles to Aizen. That role had been perfect, aside from how limiting it was in showing off his full strength.
But worried? Not in the slightest.
After all, Shuuichi knew Aizen better than anyone. This was a man who never fought an unprepared battle (the post-Hōgyoku Aizen didn't count—he let it get to his head). If Aizen said Shuuichi could take down a Captain, then it meant he had every contingency accounted for.
Sure, Shuuichi wasn't at a level where he could openly kill a Captain in a straight fight—he might barely edge out your average Captain, but not dominate them. Still, when it came to executing plans, Shuuichi trusted Aizen more than anyone.
About half an hour later, Shuuichi emerged from the lab. Only now did he understand the full scope of Aizen's previous operation.
He had underestimated the man's planning again.
Having Baraggan and Starrk lead a frontal assault on Soul Society wasn't just about creating chaos or harvesting spiritually gifted souls from Rukongai. That was just the surface.
The true objectives?
Test the results of years of experimentation.
Evaluate the combat capabilities of Soul Society's Captains.
Probe how quickly and effectively the Gotei 13 could respond to a large-scale crisis.
And most importantly: close the book on Aizen's previous research focus.
From here on, Aizen would no longer dedicate resources to the study of Shinigami spiritual particles. Meaning... Shuuichi was officially unemployed.
With that thought in mind, he started speculating on Aizen's new assignment—teaming up with Starrk to assassinate the current Captain of the Exploration Corps, Senjō Ryū, here in Hueco Mundo.
A warning to the furious nobles? Perhaps—but that was just surface-level justification.
"The real motive," Shuuichi thought, "might be to see how Soul Society reacts to the simultaneous deaths of two Captain-level Shinigami."
Because in Aizen's plan, Baraggan and Szayelaporro would eliminate the 10th Division Captain sent on expedition at nearly the same time. The last time multiple Captains were lost simultaneously? Over eight hundred years ago, during the war against the Quincy King, Yhwach.
Even during the great purge against Quincy sympathizers sixty years ago, Soul Society had only lost one Captain.
Aizen probably wasn't foreseeing the event decades later that would exile Yoruichi, Urahara, and others.
More likely, he was laying the groundwork for a full-scale purge of the Gotei 13—starting by cutting off Yamamoto Genryūsai's limbs before taking on the head.
Coincidence or not, that future incident might've just conveniently lined up with Aizen's grander scheme.
Shuuichi couldn't be sure, but he knew Aizen's mind well enough to bet that 60–70% of this theory was on point.
"Hey, little Shuuichi! So, how do you plan to deal with that annoying Recon Squad?"
As he exited the lab, the voice of Lilynette Gingerbuck, Lieutenant to Starrk, cut through his thoughts. She looked up at him with a mischievous grin, green hair bouncing beneath her skull-shaped helmet.
Shuuichi flicked her forehead with a finger. "Who are you calling little, huh? You barely reach my waist. Doesn't that embarrass you?"
"You jerk! How dare you!" Lilynette shouted, leaping up to strike back.
"Enough, Lilynette," Starrk finally spoke up, lazily. "Shuuichi—Aizen-sama said to follow your lead on this. Aside from Baraggan's personal troops, you can command my forces however you want. Got a plan yet?"
A plan?
Shuuichi wanted to roll his eyes so hard they'd fly out of his head.
You think he could come up with a comprehensive tactical plan in under an hour? Who did they think he was—God?
Still, all of that was internal monologue. Out loud, Shuuichi kept it respectful. After all, this was Starrk—"Uncle Wolf" himself. Without plot armor, a powerhouse like him could've easily survived until the Wandenreich invasion and gone toe-to-toe with the Sternritter.
"We scout first," Shuuichi said calmly. "Let's locate our target. I don't know how the Recon Corps operates, and I haven't seen that Captain fight yet. Plans come after that."