"Uh. I'll keep that in mind." Robin shakes his hand, too startled for another smart remark. It's almost a murmur: ". . . the future?"
He looks around a little more, and yes, the surreality is starting to hit him too. But hey, at least he has an ally, and besides Nightwing just walked in. Which is also weird, the guy hardly ever walks, even if there isn't exactly anyplace safe to trapeze across around here.
"Um, thanks. Water's fine." It's somewhere between a sit and a perch, but he definitely occupies a chair, and takes the chance to cock his head at the little sister. "So what's your name?" he ventures, going for cementing the alliance.