"Huh." There's so much to be said about the tragedy of losing all this that he doesn't have the context to go into in any meaningful way, besides which, this is a ghost he's speaking to, not Kenzie who suffers this absence herself.

Bunny looks at the ghost instead.

"What do you want to get out of this?" he asks. "You want her to take something from this, remember it, forget it, what's your goal with me here?"

He'll do anything he can to help any mortal, even this side of their being a child, but he's so woefully lacking in any actual communication with Kenzie. Yet here he is walking around in her own memories, uninvited.