The story is set in a world that heads toward destruction every hundred years or so. The protagonist, Lycéenne, chosen as the hero to save the world, encounters Towa, a holy woman offered as a sacrifice for the world's sake. Although Lycéenne is initially startled to discover that Towa is actually a man, she is drawn to Towa's personality and begins to worry about the future where she must kill him. Will Lycéenne choose Towa, or the world—or perhaps, both?