“What do you mean, ‘something amusing’?” he said irritably.
“Oh, surprise me,” said Slughorn airily.
Malfoy opened his copy of Advanced Potion-Making with a sulky expression. It could not have been plainer that he thought this lesson was a waste of time. Undoubtedly, Harry thought, watching him over the top of his own book, Malfoy was begrudging the time he could otherwise be spending in the Room of Requirement.
Was it his imagination, or did Malfoy, like Tonks, look thinner! Certainly he looked paler; his skin still had that grayish tinge, probably because he so rarely saw daylight these days. But there was no air of smugness, excitement, or superiority; none of the swagger that he had had on the Hogwarts Express, when he had boasted openly of the mission he had been given by Voldemort… There could be only one conclusion, in Harry’s opinion: The mission, whatever it was, was going badly.
Cheered by this thought, Harry skimmed through his copy of Advanced Potion-Making and found a heavily corrected Half-Blood Prince’s version of “An Elixir to Induce Euphoria,” which seemed not only to meet Slughorn’s instructions, but which might (Harry’s heart leapt as the thought struck him) put Slughorn into such a good mood that he would be prepared to hand over that memory if Harry could persuade him to taste some…
“Well, now, this looks absolutely wonderful,” said Slughorn an hour and a half later, clapping his hands together as he stared down into the sunshine yellow contents of Harry’s cauldron. “Euphoria, I take it? And what’s that I smell? Mmmm… you’ve added just a sprig of peppermint, haven’t you? Unorthodox, but what a stroke of inspiration, Harry, of course, that would tend to counterbalance the occasional side effects of excessive singing and nose-tweaking… I really don’t know where you get these brain waves, my boy… unless—”
Harry pushed the Half-Blood Prince’s book deeper into his bag with his foot.
“—it’s just your mother’s genes coming out in you!”
“Oh… yeah, maybe,” said Harry, relieved.
Ernie was looking rather grumpy; determined to outshine Harry for once, he had most rashly invented his own potion, which had curdled and formed a kind of purple dumpling at the bottom of his cauldron. Malfoy was already packing up, sour-faced; Slughorn had pronounced his Hiccuping Solution merely “passable.”
The bell rang and both Ernie and Malfoy left at once. “Sir,” Harry began, but Slughorn immediately glanced over his shoulder; when he saw that the room was empty but for himself and Harry, he hurried away as fast as he could.
“Professor—Professor, don’t you want to taste my po—?” called Harry desperately.