Several hours earlier, at the Twelfth Division barracks.
Aizen Sōsuke pushed open the Research and Development Bureau's metal door.
His steps were steady as he entered, neither deliberately light nor deliberately heavy.
He strolled right in.
No one looked up when Aizen entered.
He glanced around, his gaze sweeping over the rows of workstations on either side.
Data streams or waveforms scrolled across every screen. Division members in white lab coats stared at them, their fingers moving rapidly over the control panels.
His gaze finally settled on the wall ahead, where twelve large monitors hung side by side.
Surveillance footage.
Aizen walked over and stopped before the monitors.
The display was divided into dozens of smaller frames, most showing streets in various districts of Rukongai.
Soul Society was too vast for surveillance to cover every corner, but all key areas were in view. His gaze settled on the third frame in the lower-right corner.
It was playing a ten-second recording on a loop:
A Shinigami was walking down the street when his body suddenly shuddered violently. Then he crumbled and dispersed like a sand sculpture.
Without anything to support it, his Shinigami uniform fell limply to the ground in a heap.
The clothing remained.
This was not death. If he had died, his Shinigami uniform would have broken down into reishi along with his spiritual body.
His body had failed to withstand it, and even the fundamental structure of his spiritual body had collapsed.
Aizen had originally planned to continue his own research, which had indeed made considerable progress lately.
But Yan Si's hint over drinks that day had changed his mind.
A faint smile curved Aizen's lips.
Taking ready-made research directly was more efficient.
Aizen turned his gaze away from the surveillance monitors to survey the bureau. He walked