She's the only natural blonde in a program where all the other characters (IIRC) have normal Japanese hair colors. (Oh wait, also her butler's daughter, but Sumire and her father are originally of Western stock.)
Hmmm...maybe many years ago, on a private island, the Kotobukis found a little spaceship with a baby girl inside, and a universal translator device which said: "Our world, Krypton, is dying. Please take care of our daughter, Kara Zor-El."
