Yumi walked up calmly. "It was a Hollow. When a ghost stays in the world of the living too long, it turns into a mindless beast that must be put down like a dog. They seek to devour souls, like you, and living humans, like us. And if you stay in this world, you will inevitably succumb and turn into such a beast yourself." She looked to Daichi. "You know how to perform a soul burial? I notice you don't have a katana hilt anymore."