Ivy nodded, pulling her knees in in front of her as she began to explain. "Realize, the population of the city we're going to is well over a million people. I've never properly checked the numbers, to be honest. The entire population of the island you were on would fit in the tower where I live. In any case, to gain citizenship you have to take a test, proving that you're of sound mind and have a certain amount of basic education. Those who aren't citizens require sponsors to live in the city...essentially a guardian who guarantees their behavior and is responsible for teaching them."