Enjoy!
The Forgotten Lesson.
"Impediamenta!"
"Nice shot, Harry. He's out cold." Ron glowed, looking down at the prone body of Draco Malfoy. "Did you mean for him to run into the door? He's gonna have a nasty headache later."
"Worried?" Harry asked, covering his naked body with his school robe.
"Not really," Ron answered, poking Malfoy's forehead with the tip of his wand. "He won't be walking in on us any time soon. You think he'll say anything?"
"No, if he does I'll just run him into a door again." Harry said with a grin. "But just to be on the safe side. Obliviate!"
Finite.