Thai women are probably those that have the tiniest butts in South East Asia and the genetic code still works two or three generations down the lane when they mix up with other Americans and immigrants from different countries. The proportions just look different and there are many fans who admire the beauty of Thai women.
Another observation for South-East Asian beauties are facussing on their legs. In general they tend to be a lot shorter. They appear that way when pictures are taken from a high angle. Good photographers can compensate for that by picking a lower angle that will make legs look longer or by making Thai models pose while sitting or standing with different leg positions. This way they model would look less plump. But hey, there is nothing wrong with plump chicks. They do have their charme as Carolina shows.