Hermione and Ron were, Harry thought, properly impressed when he described his most recent lesson with Dumbledore the following morning. Later, using the Marauder's Map, he discovered Malfoy in a restroom—which Moaning Myrtle was currently haunting— crying that he could not do it and that, if he did not do it soon, he would be killed, as would his parents. When Malfoy looked up, he saw Harry staring. The two immediately pulled their wands and the curses and hexes began ricocheting off the bathroom walls. Harry used "Sectumsempra" against Malfoy, who fell, bleeding heavily, to the floor.
Snape came to his rescue and, ten minutes later, returned for Harry, whom he'd commanded to wait. After Snape demanded to see all of Harry's textbooks, Harry sprinted back to Gryffindor and asked Ron for his copy.....
