Joss was revealed as Carter's
first name in "Get Carter" (Season 1, Episode 9). After Carter had been shot, Reese called her Joss and told her that she was not alone. Also, Carter identified herself as Joss Carter when she called her friend in the military tor request Reese's file in "Mary Happy Returns" (Season 1, Episode 21).
I keep my hopes up for a Carter/Reese relationship. I don't hold my breath because it goes against all the TV tropes. It would not only be interracial, but (more TV-importantly) it
would be between a magazine-slick "beautiful person" and a nice-looking but more ordinary-looking person. As far as I can tell in TV-land and in movieland, it's very much relegated to dating within your own "looks" category.* If I were less naïve, I'd admit that's actually somewhat true to life.
.
Carter
could look magazine slick beautiful because Taraji P. Henson is very sexy, but the executive producers intentionally downplay her looks on "Person of Interest" because they think that she needs to look like a realistic NYC cop. Taraji naturally exudes a very sensual vibe,which probably does not fit the Carter character.
As such, they give her bulky and unflattering clothing to disguise her figure, apply very little / bland makeup, and don't really style Carter's hair.
Notice how the October 2012 TV GUIDE cover styled her to show off her curves?
In terms of looks, Carter's in the same league as Zoe and Jessica. If Carter wore the same clothing that Zoe wears on the show, eyes would be popping out because Taraji / Carter is very well-endowed.