Reid had intended to keep a straight face, but seeing Loki check under the table makes him break out into a wide smile. It's exactly this sort of reaction that he enjoys provoking from people-- harmless fun with the right audience.

"Nope. But I don't know what's customary for you, so I better not take any chances with rescued pieces." He's not about to offer an explanation unless asked, either. That would make him a very poor magician, otherwise.