In the world "Skin" takes place, there are many diverse ethnic groups. As the game begins in Arancimar, a city-state to the east of the Margato Expanse (should be a sea, but the Arancimar traders irritated a Sole magistrate who changed the official records) we will start there.
Arancimar. The "Marid" (as they self-style themselves - the epithet is "Rancid") are dark of eye, olive-skinned, and dark-haired. The royal family line has the light eyes of the elf blood that once intermingled, and once in a while a Matriarch has hints of gold or red in their hair from the same source. Elves are not unknown in Arancimar, but while they are less feared than they are in the rest of the Empire, they're still a source of awe and concern. There is a Half-elven faction within the Arancimar Alchemical Institute known as "The Gilded Irios" whose works compete with the best in the Empire. Marid are stereotyped as being foppish and slightly anti-technology.
The Erza live just west and north of the Margato Expanse and are historically likely the progenitors of the Marid, They are split between the Quilha and Placa districts, or island or continent. Quilha are more likely to ruddy hair and skin colours, with eyes just as dark as the Marid's common folk, while Placa tend to lighter skin and hair. It is said that Elves avoided the small islands of the Erza's outer Quilha (the split between the continental mass and the strange islands separated by deep canals) and thus Elves travelling in that region are regarded with suspicion. Erza are stereotyped as being sneaky bureaucrats, with the general thought of, "They can hide anything in those deep straits...and probably do." Western (Placa) Erza tend to think of their Eastern Quilha brethren as fast-talking thieves, whereas the Quilha think of the Placa as slow to speak but likely to have generation-long schemes.
North of Erza are the Teimoto, and home of the Empire's Palaces. The Teimoto live in a land covered with beautiful ghost-lit vistas and the world's most dangerous weather. Proverbs from Teimoto often reflect that if it isn't hurricane season, it must be time for blizzards. Teimoto tend to be taller, light-skinned folk, with red eyes and a trace of epicanthic fold. They're somewhat protected from the light that comes from both sky and stone. Only in Teimoto is the rare glowing Urhante stone mined. (And it's non-radioactive! Awesome pebbles of continuous light!) [Sole's Aubril crystal is the closest cousin, and makes up Sole's (Sol-ay)'s (and thus the Empire's) most lucrative currency.] Teimoto are considered stubborn and large (therefore often clumsy) but often given the backhanded compliment (from those who have been there) that the view is worth it, when, you know, not covered in rain or snow. Or fog. Or ash. Or... well, you get the picture. The First Palace of Teimoto was an Elven city, but while Elves still wander the land after the War of Teimoto Rule, they say it is not time to return.
The large deserts of the Sole and their beautiful dark-skinned people (mostly brown or darker with purple sheen) are to the South of Arancimar. Sole are categorized as extremely hard working, tough, and fair, but somewhat greedy for all that. ("Why would they work so hard if they didn't want...things?" the Erza ask.) Many Sole act as judges and arbitrators for the Empire. There are rumours of "dark elves" that intermingle with Sole, but the land is parched of anything the Elves tend to claim of value. The gentle climate of Northern Sole has the largest population, but new routes to the mostly unexplored and uninhabited Southern Island (really a continent) are the hope of the Empire's Tradesmistress. Sole's many northern states go to ceremonial war with each other regularly - few are killed, much is bet on the results, and each of the states vie for honor points. It is quite a phenomenon for the tourist.
South of Sole it is said there be Dragons.
South of Erza are the jungles of Matanouse. The Mata people gave homes to the Elves and other nonhuman species, which have made them a fairly liberal society of crossbreeds. Mata are smaller folk, skin the color of Sole's sands, with eye and hair colors all over the spectrum due to the large concentration of wild magics there. Many Mata have slightly animal features. The Marid have their rivals in the Mata College for Alchemical Artistry, and the natural bounty of the Matanouse foliage often makes for interesting reagents. The ruling Mata family have a genetic anomaly showing in their four-fingered hands and prehensile tails, and it is said that no Matriarch can rule without these traits. This leads many skeptical of their financial success to say they lie with beasts to preserve their sense of beauty. Mata are often considered promiscuous, and they treat their men as equals, so they are often discriminated against in northern territories. The Empire counts the Matanouse as part of its territory. The Mata do not always agree. The freehold pirates off their eastern coast in Adrazar claim to be Mata, and often the Mata's First Family pays ridiculous fines for their acts. If the Adrazar suffer any retribution for this, northerners do not know.
East of Matanouse is Adrazar, and the boundaries of the Empire. Not much is known of the areas past that, for too much further East lies Southern Sole Isle, and, well, Dragons.
West of Matanouse is the mountainous region of Chelonia, and those of the Chelon are not part of the civilized world. Chelonians are grey-skinned to deathly pale, and their eyes are grey to pure white, said to be the result of black alchemy they practiced in the past. Most Chelons are blind, although they may have compensated through other means. The Empire is officially at war with Chelonia, but not individual Chelon (although they can be arrested at any time.) Chelons are mostly descended from exiled prisoners of the War for Teimoto Rule, but the land has changed them.
South of Chelonia is Takatakastag which is the "place that nothing flies." Not much is known about this place, and if there are native folk here, they must look like some other group. Beware anyone who says they are from anywhere in Takatakastag. They are likely liars.