"Well, usually Rosie did it, but I've done it my fair share of times, too. It's a simple charm. No need to go spelunking or anything. I can continue to do it, or I can teach you to do it. Whichever you prefer."
Seamus nodded as Miles talked himself through what he'd be doing, but when he looked up the stairs and asked Seamus if the aurors had cleaned up properly, Seamus felt his heart jump to his throat.