Hunter just nods. He will send the other potion back to Hermione later.

He has this nervous, angry energy after trying to help Jim through the curse. And he definitely needs a way to vent. And he doesn't want to break down, where he is just yelling for the sake of yelling.

"We should only have a few more hours of this thing..." And maybe the counter-curse on the jacket is working the way it should, and the curse will end sooner than what they were told.