As I mentioned in the author note, she's been in Development Limbo for so long, I'm happy she turned out well in the end!
So, let's go a bit more into detail, shall we? Some time before I discovered the PPC I used to hang around in the Italian fandom for Knight Rider. And, at some point, I also wrote in the fanfiction section of their forum. Story was, as you can guess, a crossover between KR and Cardcaptor Sakura. Like pretty much all of my pre-PPC work it likely wasn't stellar, but I got mostly positive feedback so I think it wasn't a complete trainwreck either. The plot involved Baddies kidnapping Sakura's father while they were on a trip in America, Sakura's magic somehow reactivating the abandoned and damaged KITT, Cardcaptor and talking car managed to reunite the KR cast and rescue her father.
I'm not sure the exact timeframe in which I had written it, as while the forum seems to still exist my antivirus threw a fit when I tried opening the page and googling the title of my fic yelded no results. I do remember that after a host migration the formatting of older topics got utterly wrecked, so even if it is still up it is likely unreadable by now. I do have a copy on my PC, but various hard drive changes led to the dates on the file being utterly unreliable too (current version of the file appears to have been created in 2017, which is when I made a new computer. Last modification appears to be in August 2010, so barely after I joined the PPC, but I might had just acicdentally edted something while re-reading it as I'm fairly sure I was done with the fic before joining)
Now, I considered making a sequel for said fic, which was to set about ten years later with Sakura becoming an agent for FLAG and getting her own talking car: our ARUMI, of course, at the time still spelled in all caps since it was the acronym for Advanced Roving Unit with Magical Intersystems. I'm not sure it actually makes any sense, but hey italian teenager trying to get an appropriate English multi-word name that would sound like a Japanese name when turned into an acronym. I think I could've done much worse!
However, I drifted away from the Knight Rider community roughly at the same time I got fully invested in the PPC so I never actually wrote it. When I came up with Nikki's basic idea I considered having semi-fic blip ARUMI be her partner, but then I got feedback Sergio and Corolla were unbalanced (I think it was from you, Nesh!) and so I left Nikki with them. Arumi remained in limbo until 2018, when I eventually recycled her as one of the two agents who recruited Sergio in 2009 HST. In the meanwhile, though, I had used a variant of her name (Arumi Knight) as my handle for the single Multiverse Monitor article I wrote, so I used that as her post-recruitment name.
Which, incidentally, makes her have worked in the PPC between 1999 (A&O3) and 2013 (when she wrote for the Multiverse Monitor) at the very least - by complete accident I may have created one of the agents with the longest PPC careers! And also means I used her in a story properly for the first time more than ten years after I originally created her.