Since we're on the topic of hair...
Nathan's father is from China, his mother is from Taiwan.
I'm Taiwanese and my hair looks exactly like Nathan's -- when short, it looks straight, but as soon as it goes past a couple of inches, it starts to get very thick and wavy, and even fluffy because of how much hair/how thick it is. It is not 'fine' hair. When I used to let my hair grow longer, it would grow more shaggy and fro like -- exactly what Nathan's looks like right now.
Other than cutting it short, there is really no way to get this type of hair to "lie flat" or be straight (a la Max Aaron's slicked back Carmen and Gladiator hairdo -- Max's hair is curly, but it is much less thick/more fine and less dense and thus is willing to conform to an intense amount of product -- especially if he straightens it.)
That concludes my contribution to this hair discussion