Nemu
Kurotsuchi

Nemu Kurotsuchi is the lieutenant of the 12th Division and an artificial soul that Mayuri Kurotsuchi grew himself, using a gigai construction method and his own genetic material. He introduces her as his daughter and treats her as equipment, and she absorbs both descriptions without visible complaint.

The abuse is on screen and the series does not soften it. Mayuri kicks her, insults her in front of other officers, and modifies her body when it suits an experiment. Nemu apologises. She is also stronger than almost anyone assumes, capable of lifting weights that would flatten a seated officer, and her body carries the antidotes to her captain's poisons because Mayuri built her as a delivery system for them.

She uses that during Uryū Ishida's fight, telling him where to find the antidote on her arm after Mayuri has already abandoned the field. It is the first time she acts on her own reading of a situation rather than an order, and it is not the last. What the character eventually gets is a death that is entirely her own decision, spent forcing a way to stop Pernida Parnkgjas, and a captain who reacts to it in a way that makes clear he understood what she was long before he admitted it.