He could see some of Frank and Alice in Neville as he greeted him, though he couldn't quite put his finger on what. But Neville seemed to have a fairly decent grip on things as they stood here, or at least his own standing within all of it - and that was more than Sirius could say just yet. But he'd get there, at least he hoped so. That was part of what he was trying to do here, get more information, learn more about the world he'd left behind and how it all fit into this one now.
"So you're at Hogwarts then?" He wondered, "Or ..." He frowned not really sure how else to explain that, unless Neville was just sneaking in and leaving plants in the greenhouses for some reason. And that didn't make any sense at all so he supposed his first guess had to be the right one. "Not a student though, right?" Neville looked older, maybe older than him even, though Sirius didn't have a firm grasp on his own age at the moment, but Neville was too old to be a student that much he felt fairly certain of.
He nodded at the offer of tea, that at least was something familiar and he didn't have to think too hard about it all. "Yeah, please, that'd be brilliant." He agreed, wandering around a little bit, looking at the plants, many of them familiar from his own time as a student, and that was a kind of comfort in a world that was filled with so much that was new and he didn't understand. "Have you been here long?" The Greenhouse seemed well established, or at least the work of more than just a few weeks.