You are Kusajishi Riku, Captain of the Ninth Division of the Seireitei Court Guard. After a taxing pair of duels you and Yoruichi managed to defeat your own clones, albeit at a cost. To defeat your mirror for certain in a single move you employed your modified kidō called Yūgure Kasō, which burned away your left arm as backlash and necessitated the use of a second vial of regenerative serum.
The result however was that your own copy was completely obliterated on the spot, with not even traces of dust left behind to mark her passage from the world, while Yoruichi lured her copy into a trap and destroyed her body. The fake Yoruichi's soul, contained within a small red pill, is now somewhere on your wife's person. It's likely her intent to interrogate the pretender before handing her off to Kisuke for a more in-depth analysis. Only problem is that there's still a lingering sensation in your new left arm that bothers you.
“Your replacement isn't quite right, is it?” Yoruichi asks, no doubt noticing the slight difference in how the limb moves as you walk towards the farmhouse where the Valhallans you were tracking had holed up. They seem to have been sheltering in place there while your own battles strayed increasingly far from where they began, the rapid series of hundred-meter-long strides having made it very difficult to keep track of such details.
“Sharp eyes,” you admit, gently stretching your fingers. First all at once, then one at a time... each careful movement feels slower than it should. Clumsier, too. “The muscles are naive, but that should improve with use. Sensation's just how it should be, so that's a bright spot.”
“True, had there been lasting nerve damage it would've been worse,” Yoruichi agrees, leaning over to rap her knuckles against your forehead. “Hey, Rosa! You know what to do, right?”
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