Deep inside the pharmacy was Shinobu Kocho's private laboratory.
The lighting here was much dimmer than outside, and the air carried the peculiar mingled scent of medicinal herbs and chemical reagents.
The shelves along the walls were packed with labeled glass jars containing preserved tissue samples from various demons.
Shinobu Kocho had taken off her butterfly-wing-patterned haori and wore only her Corps uniform. At that moment, she looked less like a Hashira and more like a scholar immersed in research-or rather, a mad scientist.
"Please, look here."
Shinobu Kocho pointed to a microscope imported from the West and motioned for Sasuke to come closer.
Beneath the lens lay a stained blood sample.
Sasuke's blood sample.
"Your cells are different from those of any human I've ever seen."
Shinobu Kocho's voice held an excitement she could barely contain.
"Their activity is practically like... like that of a demon weakened countless times over. No, that's not right. They lack the invasive properties of demon cells, yet possess resilience and an affinity for energy far beyond those of ordinary people."
Sasuke calmly observed the world beneath the microscope.
Of course he knew what made his body different.
It was proof that chakra had flowed through it, the mark of the Uchiha bloodline.
Shinobu Kocho knew nothing of chakra, but her keen biological perspective had given her a glimpse of the truth.
"I agree to your proposal."
Sasuke paid no attention to her research analysis and went straight to the point.
"But there's one problem. How will you get your poison into an Upper Rank's body? They regenerate fast enough to discard the entire poisoned area before the toxin takes effect."
That was the central issue.
Shinobu Kocho's Nichirin Blade had been designed that way precisely to inject poison directly.
But against the Upper