Prussia feels kind of bad about a kid cutting himself like that, but really the blond guy reminds him of Germany with all the disapproving looks. He shakes his hand dry and pulls out his pen and notepad--crap, did it get damp somehow? stupid water--and writes a quick note on it.

No more sharp objects for you, kid!

The fact that it was his own fault for not keeping it away from him doesn't matter since obviously he thinks Barnaby should have stopped him. Then he makes a motion at him with his hand telling him to move it along with whatever lie the guy intends to tell.