Sigurd doesn't even offer a verbal reply, merely giving a brief wave of his hand. He will, however, when allowed put in an additional order with the server as soon as Björn is done with his. After that, he's silent again, sipping his water without offering further explanation as to why he's summoned the other young man here.

This isn't unusual. Sometimes it merely takes awhile before he gets to a point where he wants to discuss whatever business needs discussing. It won't be a problem to do that over a milkshake, now will it?