[And that answers his question well enough. He doesn't say aloud any of the things that run through his mind: that he knows just how he'd feel having just watched Yuuri die, or that losing Vash twice almost was too much. He can't say those things because he remembers what it was like to almost lose Yuuri and to lose Vash, and he knows that what Kaname needs is not that.]
[So, softly, he just says:] It would very nearly kill me, I think. [His tone makes clear that he knows, he gets very well how Kaname must feel losing Yuuki, and while he won't pretend that anything can help -- he knows it won't -- but if there's anything, any small amount of distraction... he's willing.]