"Sorry." Neville smiled apologetically. He understood Remus' hesitation at his offer, he probably would have been too, knowing what the wizarding world had to have been like when he came from it. But when he agreed, Neville pointed back toward his greenhouses, "I have a little set up in there, it's not much but it's close." He figured it'd be better to stay in the park until he'd been able to explain where they were, plus Remus might be a little more comfortable if they stay in a more public space, rather than go back to Neville's apartment.
"C'mon bud, we'll get you a treat too." Neville pat Ruby's side and the dragon popped back up on his feet again, grinning and eager.
Neville started leading them back to the greenhouses. There were two of them set up, with small gardens outside between them. The one he walked to was open and contained the more common and harmless plants, some medicinal, some that could be eaten, and some that he just liked. The other house he kept locked, it was where he kept anything that could be poisonous, and things that were exceptionally fragile. He didn't really think anyone paid much attention to them, but he didn't want to take any risks.
When they got to the first one he let Ruby go in first and held the door for Remus. Inside was a bit humid, but not uncomfortably so, with tables lining each wall and two more in the middle. It wasn't that far off from the set-up there had been at Hogwarts, except for the small table, fridge in the corner next to the door. Usually Neville just used it to eat his lunch when he couldn't bother to go somewhere else during the day, but it would work for this.
"Make yourself comfortable." He gestured to the table, two chairs tucked under it. "I don't have much to eat, unless you like raw fish." he apologized, going toward the refrigerator and opening the freezer and pulling out a whole fish that had been frozen solid. He held it up toward Ruby, who bounced back and forth a little, excited but still careful not to disturb the tables around him. Neville tossed the fish to him and watched as Ruby caught it mid-air, his teeth showing for just a moment before he closed down on it. "That should keep him busy for a while." The dragon walked around the table, spun in a circle, then lay down, half under it, to gnaw on the fish, while Neville went back to the counter.