[for his part, Keiwa doesn't seem to react any different to her telling him that she found the idea of diorama building fun, not realizing how important this was to her. He just smiles in agreement before he stops to think about the technicalities of building a diorama]

Hmm... They probably had a lot of practice. And a lot of patience! Apparently these can take a few months to make? And that's if they have a lot of spare time to work on it...

If you put your mind to it, I'm sure you could make something like this. And if you can't figure it out, we can always go ask this diorama maker if they have any pointers for beginners, right?

[it's hard to tell if he used 'we' to mean that he thinks she'd ask him to come along with her... Keiwa probably just figured that it would probably be better for an adult Illya knows to be present when chatting with a stranger. He's not much better with new people either, but a little solidarity goes a long way, right?]

Though... It would probably be easier to start with something smaller... Like the inside of a building or something.