It's actually a rare, but not unheard of condition, called Heterochromia.
It's probably been around forever - one of the characters in Victor Hugo's 'The man who laughs' (written over a hundred something years ago) has it.
There is a breed of cat with that condition. Also, no matter the race, there is a certain phenotype for "hot" women. Usually this is a egg shaped, oval face, kinda like a upside down teardrop. High cheekbones, full lips, but small mouth, almond shaped eyes, thick but curved eyebrows, round jawline, but a straight one can be aesthetically pleasing. And from a full frontal view, a smallish nose (men typically have larger noses than the female counterparts). For the most part, smallish but symmetrical facial features, with full lips tend to be found in all races, and men tend to pick up on those and consider women with such features as "hot", thru-out the ages...
Ever noticed that European Royalty tended to be on the ugly side? It was the commoners who had the better genes and better breeding---in terms of looks.