For centuries, the great clans have fought to maintain a fragile balance through strength, tradition, and elemental power, surviving generations of bitter war only for an ancient threat to stir beneath the surface. Kuragari Kagetsu and Kiyoshi Nanemori enter the Eos Examination to prove their strength and protect those they care about. Alongside the abrasive Raimane Eto, they are thrown into a trial where rivalries are born, and the world's order begins to crack.

As Team Eos takes on missions, they uncover the Kurotsugi, a secretive group whose motives are as incomprehensible as the horrors they leave behind. This scattered investigation slowly reveals a dark conflict rooted in history, threatening every clan and nation.

With each battle, the line between justice and vengeance blurs. Yamiuta is a dark epic about conviction, grief, and the heavy cost of trying to hold a breaking world together. If the world demanded everything, would you still save it?