Karna is also a character from the anime NieA Under Seven. She is very concerned with increasing the status of aliens in the Enohana area, so she's bothered by the freeloading antics of that no-good antennaless Under Seven NieA. This rivalry is all the more absurd because they're so much like eachother- they both yell a lot and are good at pointing at people. She also likes traditional Chinese clothing and, apparently, Genzo Somemiya, which leads to friction between her and Mayuko Chigasaki, who is oblivious to Genzo's affections.
I think she's a communist.
Like all Yoshitoshi ABe characters, Karna is beautifully designed.