Borrowing Fate from the Future

At the center of the universe lies the 'River of Ages,' which runs through all worlds. The River of Ages is divided into three sections: the Upper Reaches, the Sea of Unknowing, where all possibilities that have not yet occurred reside; the Middle Reaches, the Present World, where reality is currently unfolding; and the Lower Reaches, the Abyss of History, where events that have already happened and can no longer be changed are stored. Whenever a living being makes a truly important choice, several future branches are generated in the Sea of Unknowing. Ultimately, only one becomes reality, while the other futures dissipate and return to the Sea of Unknowing. Thus, the most essential resource in this world is not spiritual energy, but the possibility of making choices. — Description from novelcodex.org