Katsuya seems more than a little surprised at how loud the bang is, though it's punctuated by a laugh when a paper hat falls in his face.

"What is all this? A muggle cracker? Are these jokes?" Some of the puns may have to be explained to him, despite his fluent English some things do still get lost in translation. They're awful jokes, but in a good way!

Katsuya laughs.

"I don't know what I was expecting, but I'm pleasantly surprised."