It was a good life, Sonata thought to herself. The Canterlot High Not A Human Testing Installation, John Q. Discord's personal playground of semi-responsible experimentation, was certainly one of the more interesting places she'd ever been to. Food was plentiful, her salary was apparently respectable, and Mr. Discord himself emanated an aura of confused emotions that Sonata could at least appreciate, if not actually consume.

And yet...

And yet. Really, the fact that Sonata even got that far was enough to make her furrow her brow. Just a few months ago, she'd have taken her current circumstances with both hands and her jaws and held on for dear life. Indeed, when Mr. Discord had made the offer, that was exactly what she'd done. But then the Friendship Games came and went, and they'd left more than occasional reports of bony-plated monsters in their wake.

The usual pleasures of life had started to dull. Sonata's growing bank balance—something Mr. Discord set up for her, like the important-looking papers from that nice man in the alley—meant little to her once the novelty of seeing her numbers go up had worn off. It wasn't like she actually needed the money for anything. Messing with students at Canterlot High grew both harder and less fun as everyone grew used to the girl with the serrated teeth. Even food didn't bring her any happiness these days. The last time Sonata remembered tasting anything was the apple-habanero salsa the lunchlady had asked her to sample one day, and that was last week.

And then there was the conversation with those two not-dating girls...

Sonata paused as her body, long used to working while her mind wandered, finished adjusting the wiring on one of the science colanders. "Mr. Discord?"

He looked up from the notebook where he was scrawling a draft of his next book. "Yes, Sonata?"

"Did you do something to me?"

Mr. Discord quirked an eyebrow. "I've done many things to you. Did you have anything particular in mind?"

"Like what you did when I tried to pounce on you."

"Not since then. Why do you ask?"

Sonata fidgeted and carefully chewed her lip. Her fangs had torn through it the first few times after the change. "How come you've never asked me about what I know about magic?"

"Mostly because I haven't gotten around to it yet," he said with a shrug. "This world's magic is, as I understand it, unprecedented on a multiversal scale. The sheer quantity of topics to investigate is almost overwhelming, and before I can see how your knowledge and experience compare to our current circumstances, I need to see what those circumstances actually are. Otherwise, you could lead us to dead ends through no fault of your own." After a moment, he added, "Also, you never asked until now. Why, what do you know about magic?"

"Oh." Sonata wrung her hands. "So it's not because you just think I'm dumb. And useless. And the cow totally kicked over that lantern in Whinnycity."

Mr. Discord smirked, but it was one of his friendlier smirks. "I get the feeling we aren't actually talking about your contributions to thaumology."

"I think I'm sick. With some weird human disease."

"And thus we come to why you thought I'd toyed with your mind again." Mr. Discord stood and looked her over as he approached. "I'm not picking up any notable conflicts in your immune system, but I could be wrong. What are your symptoms?"

"It's Adagio and Aria. I can't stop thinking about them. I left them because we didn't have any reason to stick together anymore, and even before that they only kept me around because we couldn't feed without one another. I knew leaving was the right thing to do. I was so sure... but now I'm not. I keep wondering what they're doing, how they're doing." Sonata sighed. "They probably didn't find any nice, rich guys to look after them."

"I do hope that's not how you describe our relationship when someone asks."

"They were the worst, but I... I think I miss them." She stomped the floor, fists shaking. "And that doesn't make any sense!"

Mr. Discord shook his head. "I'm afraid it does. Sonata, what you are experiencing is that strange human emotion known as guilt."

"How do I make it stop?"

"In my experience, you have two options: Let time bury it until you can ignore it more often than not, or try to fix the cause."

Sonata considered this for a few moments. "How much time?"

He shrugged. "Depending on the nature of your guilt, it can take anywhere from hours to decades to eternity."

"Okay then. I guess I'm going to have to see how the others are doing." Sonata nodded to herself and made for the door.

As her hand reached for the knob, Mr. Discord spoke up. "Question: Do you have any idea how to go about doing that?"

Sonata went still. After several seconds, she let her arm drop and the rest of her droop. "No."

"Then I'll be happy to lend my assistance."

She turned back to see him smile. "But—"

"I'm afraid I won't take no for an answer." Mr. Discord stuck out his thumb and pinkie and held them to his head like a phone. After a pause, he said, "Hello, Celestia. Do you remember that time in ninety-eight when you and Luna were stranded in Las Pegasus and you had to call your dear uncle to bail you out with nary a word spoken to your parents?" A pause, then a chuckle. "No, I'm not calling in the favor; I just like reminiscing. I'll be using my vacation days this week. The substitute just needs to prepare everyone for finals. Then possibly administrate them; I'll keep you updated should this go for longer than I expect. Ta ta." He shook out his hand, smirking. "The telecom companies hate it when I do that."

Sonata stared. Not because of the magic; she was used to that from him. Something else perplexed her far more. "Why are you helping me with this?"

"Firstly, you're welcome. Secondly, I can't have my lovely assistant distracted by guilt when we have such vast, uncharted realms of knowledge to explore. Thirdly, this sounds incredibly interesting, and I could use an airing. It's all too easy for me to get so cooped up in here that I all but forget the rest of the world exists as anything but a source of data. Oh, and, fourthly, I believe we established that you have no idea where to find the other sirens."

"Uh..." Sonata squirmed. "I was going to ask Sunset Shimmer."

Mr. Discord quirked an eyebrow, then adjusted it when it started to slide off his face. "The same girl who couldn't find you blindfolded?"

Sonata sighed and nodded. "Why did I have to wear the blindfold in that experiment, anyway?"

"It amused me. My point is that if Sunset couldn't detect any of you last month, she likely won't be able to now. No, I have a better idea."

"Chaos magic?"

"Well, it might help," said Mr. Discord, scratching at his goatee. "Or it might turn us into a blue whale and a bowl of petunias. No, I was thinking of something far more reliable."

"The Internet!" cried another instance of Mr. Discord from within the data analysis portion of the NAHTI.

After a flash of light, Sonata found herself standing behind him. "Oh. I guess that makes sense."

"Given how you three tried to lay low up until your attempt to consume the school, any hits on your names should either be coincidences or very recent developments." A few keystrokes later and Mr. Discord beamed. "There we have it!"

Sonata peered over his shoulder. "I recognize Aria's name, but who's Police Blotter?"

"While I'm sure there are more than a few people with that name, in this case, it's just a record of arrests and other events around a police station. And would you look at that, there's a Blaze in Bloodstone!"

Sonata grinned. "Ha! Who kicked over the lantern now, Aria?"

Mr. Discord glanced at her. "I honestly can't tell if that was clever or a misunderstanding."

"... Yes?"

"I'm training you well," he said proudly. "In any case, it will be a simple matter of getting you there to gloat in her face; Bloodstone's not even an hour away." A bit of time passed as Mr. Discord tried other search strings, resulting in ever more frustrated grunts and nothing else. "It appears Adagio Dazzle will be harder to track down. Do you know what this means?"

"I can try curing my guilt with just one of them?"

"Close. Road trip!"

Author's Notes:

As you may recall, when Mr. Discord offered to make a personal contribution to CHS, Principal Celestia told him it could be anything, so long as it was not a human testing installation. Thus, the NAHTI.