[ Rafa keeps his hand, pleased by his excitement. It's probably nothing to be pleased over, but it's obvious Max likes his interest in the car. He leans in, seeing the engine and...all of the parts. And tubes. And canisters of what looks like water, but probably is not. He looks up, expression disbelieving. ]

So you are saying it explodes, over and over again, and that is what makes it move.

Like a firework.

[ That being his main experience of things that explode. He looks at Max, lifting one very expressive eyebrow. ]

It sounds like magic, and that never makes sense. [ But then he grins. ] Show me how it works. Please? [ He slides closer, his free hand touching Max's waist. ]