In the darkness there is breathing, and the sounds of supine bodies shifting in their rest.
Outside their cave of blankets not one low whisper, or small slick noise escapes. A hastily and inexpertly cast silencing charm has displaced them all to a corridor on the floor below. The effect there is that one of the stone gargoyles seems to be making sucking noises.
"Are you sure?" The question is heavy with need, lust, and uncertainty.
"Bloody hell, yes!" comes the answer, urgent with desire and recklessness.
Had they been capable of it, the thought of such reversal in their usual characters might have amused them. The one usually so bold and careless in his actions, the other mothered to a degree of caution and self doubt; but now all thought has melted to the primal flow of skin on skin.
The gargoyle sounds like it is working furiously on a whole bag of sherbet lemons.
"But won't it- I don't want to hurt you- we never…"
"Don't worry, Harry. I thought of that."
There are fumbling noises as large, blunt fingertips scrabble for a wand; a curse as it clatters to the floor, a triumphant grunt as it is retrieved, and then-
"Lubricus!"
A shocked second's silence.
"Lumos!"
The blankets fly back, sending an arcing spray of thick, heavy, translucent gobbets across the curtains of the bed. Plump drips fall slowly onto its occupants, now sitting waist-deep and plastered in slippery goop.
They wipe slime out of their eyes and look at each other.
"I'm going to kill Fred and George," Ron mutters ruefully just before the laughter erupts from Harry.
On the floor below, moonlight stretches the shadows. The Potions Master is completely unobserved and therefore permits himself an unadulterated smirk as he stands with his head beside the gargoyle's, considering adding a Priapic Potion to the following day's lesson plan.