There is recognition in his expression when Roxas mentions Ryslig, but not for the reasons he hopes. He's heard that name before from someone else that he's had a rocky start with. There has to be a connection there, right? Maybe Roxas knows something about this Vanitas.

"No. I've never been there. But it's interesting that you're not the first person to ask me that." Well, Vanitas hadn't asked so much as assumed. He studies Roxas closely as he speaks, looking for any indication that he might already know who Riku is talking about. And if for any reason he doesn't...well, he should at least be informed that there's a spider monster running around with Sora and his face.