Harry Potter and the Methods of Rationality

"Why didn't you tell me any of this?" Hermione said, and despite herself, her voice rose in pitch. "If I'd known -"

"It wasn't my secret to tell you," Harry said. "Draco's the one who would've been at risk, if his father had found out."

"I'm not stupid, Mr. Potter. What's the real reason you didn't tell me, and what were you actually doing with Mr. Malfoy?"

"Ah. Well..." Harry broke eye contact with her, and looked down at the library table.

"Draco Malfoy told the Aurors under Veritaserum that he wanted to know if he could beat me, so he challenged me to a duel to test it empirically. Those were his exact words according to the transcript."

"Right," Harry said, still not meeting her eyes. "Hermione Granger. Of course she'll remember the exact wording. It doesn't matter if she's chained to her chair, on trial for murder in front of the entire Wizengamot -"

"What were you really doing with Draco Malfoy?"

Harry winced, and said, "Probably not quite what you're thinking, but..."

The horror scaled and scaled within her, and finally broke loose.

"You were doing SCIENCE with him?"

"Well -"

"You were doing SCIENCE with him? You were supposed to be doing science with ME! "

"It wasn't like that! It's not like I was doing real science with him! I was just, you know, teaching him some harmless bits of Muggle science, like elementary physics with algebra and so on - it's not like I was doing original magical research with him, the way I was with you -"

"And I suppose you didn't tell him about me, either?"

"Um, of course not?" Harry said. "I've been doing science with him since October, and he wasn't exactly ready to hear about you then -"

The inexpressible sense of betrayal inside her was welling and welling, taking over everything, her rising voice, her glaring eyes, her nose that she was certain was starting to run, the burning in her throat. She shoved herself up from the table and took a step back, the better to look down on her betrayer, and her voice was very nearly screeching as she yelled, "That is not okay! You can't do science with two people at once! "

"Er -"

"I mean, you can't do science with two different people and not tell them about each other! "

"Ah..." Harry said cautiously. "I did think of that, and I was very careful not to get your research mixed together with anything I did with him -"

"You were being careful." She would have hissed it, if it had contained any Ss.

Harry raised a hand and rubbed at his messy hair, and somehow that made her want to scream at him even more. "Miss Granger," said Harry, "I think this conversation has become metaphorical on a level that's, um..."

"What?" she screeched at him, at the top of her lungs inside their Quieting barrier.

Then she realized and got so red that if she'd had an adult level of magical power her hair would have spontaneously caught on fire.

The lone other patron in the library, the Ravenclaw boy sitting in the far opposite corner, was staring wide-eyed at both of them while making a rather sad attempt to conceal it by holding up a book just below his face.

"Right," Harry said with a small sigh. "So, keeping firmly in mind that it was just a bad metaphor, and that real scientists collaborate with each other all the time, I don't think that I was cheating. Scientists often keep quiet about projects they're working on. You and I are doing research that we're keeping secret, and there were reasons not to tell Draco Malfoy in particular - he wouldn't have stayed around me at all, in the beginning, if he'd known I was your friend and not your rival. And Draco would've been the one at risk if I'd told anyone else about him -"

"Is that really all?" she said. "Really, Harry? You didn't want both of us to feel special, like we were the only ones you wanted to be with and the only ones who got to be with you?"

"That was not why I -"

Harry paused.

Harry looked at her.

All the blood was rushing back into her face, there probably should've been steam coming out of her ears, which in turn should've been melting off her head with the liquid flesh running down into her neck, as she realized what she'd just blurted out.

Harry was staring at her in dawning and complete terror.

"Well..." she said in a rather high-pitched voice, "it's... oh, I don't know, Harry! Is it just a metaphor? When a boy spends a hundred thousand Galleons to save a girl from certain doom, she's entitled to wonder, don't you think? It's like being bought flowers, only, you see, rather more so -"