The world has emerged from the Twilight Century, a hundred years of humanity striving to survive after rising seas and oil wars devastated entire countries. In New Qian, part of the Scandinavian Union, natural snow and ice now exist only in historical books. Fresh, untainted water is a precious resource, citizens' personal quotas strictly enforced by the armed water guards. Noria Katio is an apprentice tea master. When she turns seventeen, she is entrusted with a secret - the existence of a hidden freshwater spring nearby, preserved by her family for generations. But as Noria takes possession of the knowledge, she holds the fate of everyone she loves in her hands...