[ Hermione's expression falters and she frowns, arms slipping across her chest as she stares him down. There's no need to be so particularly rude and, honestly, she wants to give him a stern lecture on how to treat people who are just being polite. For now, however, she purses her lips and keeps that held back. ]

And yet no one around us is fainting because of a sleeping potion or passing out because of a Draught of Living Death, are there? I think if we were being poisoned it would be a little more obvious, don't you?