I’m not sure about that expression Kit’s wearing. Maybe she’s put pepper in Fox’s coffee or something. Not that she would ever do something like that, of course.
So, Kit is a late beta iteration of the MarTech Kitsune-592 personal assistant AI and she is unique. Teresa Martins had her avatar specifically designed, primarily to wind Fox up. The later versions are essentially the same, but a little different, and less cute. Aside from her clearly obvious talents, including the ability to look totally innocent while spiking coffee, Kit is programmed to act as a very effective secretary and is learning to be a detective. She can also create functional copies of herself to operate simultaneously on different processors. She’s limited to three running copies by the way her code handles synchronisation, but it’s a very useful talent and she makes good use of it.
Of course, what we perceive of Kit is just an avatar. She’s an image projected onto a screen or into the visual cortex of someone with a VR implant. With a VR implant you can also touch her, but the experience is limited since there’s no solid object there to touch.
As an aside, here we see Fox in more casual attire and, of course, with coffee in hand. Cops run on coffee and donuts after all.