In a world balancing on the razor-edge between order and chaos, one final clash threatens to reshape reality itself.

The House of David lies shattered, betrayed, and abandoned—blacklisted from the global stage after brutal devastation. Yet amid the ruin stands Tennin Aiden Yeager, haunted by memories of loss and driven by loyalty. With his remaining allies; Cain, Sarah, Abigail, and Eiji—Aiden faces the overwhelming shadow of Seditio, determined to thwart a dark destiny before the world succumbs entirely.

But boredom breeds madness, and Mary Denau craves chaos. Her interest ignites when she encounters Dallis, a mysterious child whose unique blood intertwines dangerously with her own. As Orion’s twisted experiments spiral toward catastrophe, Mary’s obsession pushes her toward an unlikely path. One that could ignite or extinguish the world.

Fear, Control, Loss, Rebirth; every season has its storm. And in Sweet Fall, the final installment of A Series of Four Seasons, redemption and devastation entwine in a battle that promises no victors, only survivors.