History
Naomi Kimishima was originally a brilliant Japanese surgeon, but news of her supernatural Healing Touch ability branded her a "devil doctor" and ruined her career. A shady organization called Delphi relocated her to America, giving her a new job under the assumed name Nozomi Weaver in exchange for her skill and Healing Touch. While she didn't agree with their ideology (medicine was wrong, cultivating and unleashing a deadly disease known as GUILT was practically a religious mission), she owed them for salvaging her a new life. So they told her to do things, she did them, and they paid her.
Meanwhile word came out of another brilliant doctor with the Healing Touch (suddenly more acceptable, go figure): Derek Stiles, who had recently begun working with international medical research organization Caduceus. Each time Delphi unleashed GUILT, Caduceus stopped it. When Naomi was effectively discharged from Delphi and left with a sample of GUILT, she jumped ship. She went to Caduceus Europe and gave them her sample and her skills (including her Healing Touch and other knowledge) for full amnesty for her crimes. For months after that, she treated GUILT patients and did research part-time, all under her original name again. This gave her time and freedom to struggle with what she’d done in life - she felt she had to atone for what she’d done with Delphi, but after all that did she really deserve to be a doctor?
When Derek Stiles became infected with GUILT while in Europe, it was up to Naomi to operate on the international hero of medicine. She realized that yes, she too was needed as a doctor no matter her past, and to work as a true doctor again would be her atonement. When she confided all this - her past, her thoughts - to Derek, his trust never changed and she pulled through. Derek was cured and ready to work again when another outbreak occurred, resulting in a team-up effort to treat infected patients.
Naomi stayed in Europe for a year or two believing that she would not receive amnesty elsewhere, but when she became infected with some kind of disease Derek probably pulled some strings to help and with a plea bargain Naomi was able to stay free in the US on the stipulation that she oblige to any government demands for her work. Her time was short: Derek couldn't treat her illness, so she had a year left at best. The illness made operations dangerous, so instead Naomi found work as a researcher at the Cumberland Institute of Forensic Medicine in Maryland Maine.
The FBI began to call on her at CIFM to work on murder cases, and her FBI liaison turned out to be a former Delphi coworker who'd faked his way into government work. Unfortunately stuck with him, Naomi imposed a ban on discussing their past and nicknamed him Little Guy; a working relationship developed from there as Naomi did her job and solved cases. She gained a reputation for her work and her ability to hear the dead's last words (presumably developed in the time between Second Opinion and Trauma Team), and became infamous when she took a serial bomber’s case and the media dubbed her the "Corpse Whisperer." This was a bad thing, as the bomber knew to send her an explosive that caught Alyssa Breslin, the sweet little girl who had befriended Naomi, in its detonation and burned down Alyssa’s house (with her parents in it).
Naomi was angrier and more frustrated than she'd ever been: she was desperately afraid that Alyssa would die, and blamed herself for getting the Breslins involved. It was a little while before Naomi was able to snap back to herself and track down the Raging Bomber to atone again - this time, for what she'd done to Alyssa. Alyssa survived, and Naomi took custody of newly orphaned Alyssa reasoning that the FBI owed her for her work and that it ensured that Alyssa wouldn't be abandoned: upon Naomi's inevitable death, the FBI would be left responsible for her care.
Before they could leave the hospital, a mysterious disease that had appeared in some of Naomi’s past cases quickly became widespread. Naomi and Resurgam staff determined that the disease had been cultivated from the blood of Rosalia Rossellini, adopted daughter of virology researcher Albert Sartre. Both were already dead, but they managed to procure an antiserum to counter the Rosalia virus.
However, somewhere in her work with Rosalia and Sartre's bodies Naomi became infected with Rosalia. She ignored her symptoms to work on the antiserum, but the virus mutated in combination with the disease she already had and she soon collapsed. Resurgam was able to treat her, and in doing so eliminated her original disease along with it - leaving Naomi able to live freely and enjoy another chance at life.