Nury is a smuggler who helps refugees escape China in the early days of the outbreak. As a character, he doesn't get much development beyond a love of money that turns sour as he witnesses more and more horrific sights. But that doesn't mean his story isn't important to the story as a whole.
See, he's what we'd call a world-building character. His exploits into human smuggling help us understand how the zombie infection spread beyond China despite the People's Republic's best efforts to stop it.
His story about how ship captains would dump whole cargo holds of zombies on foreign shores or right into the ocean explains how zombies could just suddenly appear on beaches in places they shouldn't belong. He also tells us that corrupt government officials took bribes, allowing containment policies to fail around the world.
And check out this statement about the "refugee's heart":
These people were desperate. They were trapped between their infections and being rounded up and "treated" by their own government. If you had a loved one, a family member, a child, who was infected, and you thought there was a shred of hope in some other country, wouldn't you do everything in your power to get there? Wouldn't you want to believe there was hope? (2.2.18)
We find this quote so important, because these refugees don't get to speak for themselves. Since they end up as zombies, and zombies are notoriously tight-lipped, we don't get many changes to empathize with them. Through Nury, we're able to glimpse at the human side of the refugees. And that's no small task, considering that their zombie chops will soon be sinking into many another person's skull cavity.