A world consumed by monstrous insects. A warrior wielding a blade imbued with ancient spirits. Ren Sato, a young man haunted by an unknown past, is humanity's last hope. As a Kinshi, he must master the power within his katana to protect the innocent and unravel the dark secrets of the Kairo, a terrifying plague. But the line between hero and monster blurs as Ren descends into a world of shadows, where his own humanity is tested at every turn.
Ren enters the ritual chamber, facing an unknown ordeal. During the intense ritual, he experiences visions of his father, urging him to be strong, and encounters the souls of the katana, demanding proof of his worthiness. After enduring the trial, Ren emerges from the chamber transformed, ready to embrace his new path as a Kinshi warrior.