That 'thing'. Even as she clings to him, his attention having turned at the slight movement he furrows his brow in concern over all the little pieces he's putting together and formulating an answer. And although Saitou can't bring himself to try and pry her away from him and put distance between them, that lack of recognition of the grand master alone makes him feel immeasurable doubt ( because it was so obvious she adored Hijikata in so any ways and would give the world to him if she could; she was one of them in a world far below where he was placed but she refused to let go and accept that, always pushing herself one step further and drawing everything when doubt overcame her back to the strength and capability to save him.

"You... Do not sound like her," Saitou finally says, flat and emotionally void but his body language is not tense with the anticipation or realization that he's made such.a gave mistake he understands now. It's impossible to tell, variations are so different. He's missing something and not just he suddenly strongly feels this is not the woman he came here with and he's rapidly shaking his brain for something previously occurred beyond the inscription to understand the sacrifice ( the woman, the altar ) and its meaning. "I... won't kill her," he sighs. They kill enough that he does it only when absolutely necessary. In truth, he feels he will have to in one form another but that is not this instant where he is not past any reason of doubt he knows which to point his sword at.

"The creature may be the only thing left that can give is hope to escape by locating the exit. We can't risk losing that."

Chizuru also would have such a hard time demanding he kill something or someone when it's not even being aggressive or able to defend itself. Life was too important for such flippant accusations and wishes.