He jumps a bit when she shouts, staring a moment when the cards hit one of the 'trees' and shakes a few petals loose from the flowers.

"Ah," he finally says after a few moments. "See, we have something similar. We just call that Expelliarmus."

It's just habit to do the hand motions as well, even without a wand. Which means that the clipboard one of the 'trees' was holding went flying. Remus blinks, then huhs. "Well. That's another spell I still have, apparently."