"...Severus. Harry."

"Headmaster! I... umm... This isn't at all what you think. I was just--"

"Mr. Potter, I think the Headmaster has a fair idea of what is going on here. It is quite obvious, wouldn’t you say."

“No, I don’t think it’s quite obvious! This looks—It’s—I—“

"Severus, in my many years of living, I have found that there are only so many things one can do with one's pants around one's ankles in a dark room. Only one of them is coming to mind right at the moment."

"Yes, that's a very good point Headmaster, but we really weren't--"

"What Mr. Potter is trying to so eloquently explain is this. In a similar situation - involving an entirely different party - he has developed a bit of a rash. Do you see those red bumps there?"

"Ah, I do now that you point it out. They are unpleasant looking aren't they? Are they itchy?"

“It appears as though they just ooze a bit.”

"Kill me. Now please."

"In good time. As I was saying, I happened to notice the boy's mot exaggerated discomfort in class today and offered my services. It appears he’s too embarrassed to go to Madame Pomfrey. Hence the--"

"Yes. Quite. Well, carry on then. And do try to be more careful, Harry. That really does look painful."

"Yes, Headmaster."

After Dumbledore left, Snape snapped on his other rubber glove, looking down at Harry with a very smug smile.

"It's a good thing he came when he did. I'd hate to think what would have happened if he'd caught Draco here too."