Employee of the Facility. Handler of X-23 during her time there.
Kimura was born to an abusive alcoholic father and a negligent mother. Her life at home also mimicked her life at school, where she was also abused and tormented by her peers. Through unspecified means and at some point in time, Kimura's grandmother became her caregiver. At once, her grandmother tried to heal the emotional damage inflicted upon Kimura through nurturing, love, and understanding. However, by that point in time the emotional scars were permanent and her grandmother's attempts to reach her were futile. After her grandmother's fatal heart attack, Kimura took off, eventually coming into contact with the Facility. She then underwent some unspecified procedure that granted her physical invulnerability, density control, and reconstruction. She then exacted revenge against those in her past who had wronged her. During her time at the Facility, Kimura eventually assumed the same abusive role as the people who victimized her in the past, particularly Laura (X-23).
As an agent of the Facility, Kimura became X-23’s handler. She abused X-23, finding any excuse to bully her, regardless of whether X-23 failed or not. After X-23 escaped the Facility, Kimura made it her duty to track down X-23, bring her back to the Facility, and kill anyone X-23 has come in contact with.
She eventually tracks X-23 to San Francisco, where Laura is living with her Aunt Debbie and her cousin Megan. During a raid on Debbie’s house, Kimura breaks X-23’s neck. She then uses adamantium handcuffs to handcuff herself to Laura and drags her downstairs to Debbie and Megan where she hurts Megan by using her powers on her. Laura recovers from her injuries, cuts off her own hand and handcuffs Kimura to a pipe. Laura then stabs the pipe and leaves the house with her family and watches as it blows up.
Eventually she tracks X-23 to the Xavier Institute for Higher Learning, Kimura proceeds to lure “her” out in the open so that she can capture her but it eventually turns out Kimura is actually after Mercury who is captured. She and X-23 fight but she injures Laura and gets away with Mercury.
When she arrives back at the Facility, she watches as they test their new experiment, Predator X upon the mutant, Mammomax, much to her pleasure.
Eventually, X-23 and Hellion track her to the Facility. She uses a sonic device that only mutants can hear and stabs X-23 in the shoulder. Hellion picks her up and smashes her into a wall. Laura tells him to kill her but he refuses so he uses his telekinesis to throw her away.
Kimura, eventually makes her way back to the Xavier Institute and makes another attempt to kill X-23, Emma Frost comes across her and mind-wipes her, making her forget about her grandmother--the only influential and positive person in her life. Emma tells Kimura that she is nothing but a bully who is trying to harm others to make up for her own sad childhood full of sorrow and being bullied. Emma controls Kimura’s mind and makes her hunt down the leaders of the Facility, particularly Professor Harkins who oversaw the experimentations done on Mercury.