Because Rei was a spirit, the only thing that could fight against it was the same entity. The entity that held the same power and strength like him and it was Lu.
This very moment was the very reason why Lu was there with them.
Cane knew that the lycan was their only way out to win against Rei and he knew what the sacrifice that was required for that to happen.
Right now, Lu's spirit handled Rei's and the lycan had completely out of Cane's body, as the alpha dropped to his knees.
He didn't feel any pain, but he felt like there was something missing, as if he lost an arm or leg. This was not a comfortable feeling.
Right now, above them, the black wisp hovered above them, covered the night sky. There was this streak of red light, occasionally that you could see.