It's a good thing he is capable of reducing his reactions where others would betray themselves much more, but even Saitou as he approaches the altar to come and kneel down by Chizuru, bringing a hand immediately up to the injury at her neck before glancing up at the altar where the other Chizuru is lying still.

"...Take its place?" There's a lot to try and understand here, her words and he doesn't know what she means by friends or even the question on the creature waking up. "Yukimura... wakes from what?" What even happened to make it unconscious in the first place, if that's what is going on here.

He would have imagined that with the slit throat and the steady subtle breathing that its passed out from blood loss and not... well, not in any position to do much waking. He has a bad feeling about this, but with Chizuru's wellbeing at stake he can't do anything but follow whatever motions necessary to be most likely to save her. Starting to hold doubts and skepticism are not going to win him any favors in terms of her safety,that's for sure.