At that very moment.
At another reserve Ubuyashiki Estate.
Kagaya Ubuyashiki sat quietly in the corridor.
Suddenly, he felt an extraordinarily strange itch across the skin of his face. The ugly purple curse markings that had tormented him for decades, spreading like tree bark, actually began to recede at a visible speed.
His breathing became remarkably easy, and the feeling of decay in his lungs vanished without a trace.
Kagaya slowly opened his eyes.
His eyes, once clouded and completely blind, now focused again. He clearly saw the wisteria in the courtyard and the golden sunlight spilling through the gaps between the leaves.
With Muzan's death, the Ubuyashiki Clan, tormented by the curse for centuries, was finally freed completely from its shackles.
Kagaya Ubuyashiki stood and took a deep breath of the wonderfully fresh morning air. Tears slid silently down his face.
"Children... you did it." Kagaya's voice was very faint, yet filled with boundless relief and gratitude.
Sunlight poured unreservedly over the battered land.
The ruins of the Infinity Castle looked particularly glaring in the morning light. Amid the shattered walls, the once-arrogant demons had been reduced entirely to ash beneath the sun, without leaving even a trace of a struggle.
There were no more demons in the world. The terrifying nightmare that had plagued humanity for a thousand years had finally come to a complete end today.
The Demon Slayer Corps' Kakushi Corps members were clearing the battlefield with barely concealed excitement. Many wiped their tears with dust-covered sleeves as they carried away rubble.
Those tears held the joy of victory and relief at having survived. They carefully lifted the injured swordsmen onto stretchers and set off toward the Butterfly Mansion with steady steps.
All the Hashira had suffered extremely serious injuries in last night's fight to the