Yuuki Yuuna wa Yuusha de Aru: Dai Mankai no Shou

After the Hero Club's battles, Yuna and her friends finally enjoy days that resemble ordinary school life, but the peace surrounding them was built on sacrifices they never fully saw. Two years earlier, Mebuki Kusunoki trained to become a Hero and lost the position to Karin, only to later be appointed commander of the Sentinels, a unit ordered to explore the unknown land beyond the barrier. There, Mebuki and her team discover how much danger others have carried so humanity's small remaining world can survive. Stories of those who fought at the center and those kept outside it begin to overlap, revealing that victory was never one heroic moment but a long chain of painful choices borne by many different people.