[Sousei slowly crosses his arms at that, giving Yata a flat look.]

That is none of your concern.

[He says that to make his point--Yata doesn't have the right to ask these things. But he's going to tell him anyway, because he can tell that Yata simply cared about Nishiki.]

She is from my world, and is the ward of my protege. As she protects and cares for him, I owe her the same in return.