Bella doesn't even have a tray yet but the sign is very arresting. "No kidding?"

"The genuine article! Five days guaranteed, actual duration somewhere between five and ten. Retention is good after the effects wear off, better if you rehearse the material that day. Going rate is six mana-hours a pop, a mana-hour is approximately one average freshman doing exercise or math problems or Codenames for one hour, I tested it back home because we need a measurable currency in this place - " he places a small glass bead on the table "- I also take spells and enchanted stuff and specific favors and occasionally suggestions. This is as cheap as they'll ever be, by the way, I've got to wow people with 'em before I start jacking up the price." 

"Jesus. Can I dibs one for after I've gotten six hours worth of math problems to do? I've got Econ in Mandarin and also geometry today, it might add up to enough by this evening. Do they have a good shelf life?"

"Shelf life is terrible, unfortunately, but they'll keep 24 hours. I plan to sell a new batch every ten days or so." 

"This batch is 24 hours from when, then?"

"About an hour ago. It's a rough estimate, I wouldn't necessarily trust them at 6:55 tomorrow. To be more specific, the efficacy decays a little bit over the day but starts to drop off sharply at the 24-hour mark. Mostly the duration suffers." 

"Okay. So if I go ask the sophomore from my enclave to spot me the mana and I drink it now it'll be better?"

"Little bit. Basically you'd get the benefit of the effect for your classes today, without much effect on the endpoint. But if you drank it at noon tomorrow, you'd be lucky to get two days." 

"I'll be right back." She sprints after Suze. "Suze! Suuuuuze!"

A boy with a power-sharer who's been eavesdropping walks up. "I'd like," he does some brief mental calculations, "five, please."

There goes a lass who knows a good opportunity when she sees one. He takes advantage of the pause to snag some hash browns. 

The newcomer catches him mid-mouthful. He takes a moment to swallow. "You heard the part about the shelf life, right? Don't wanna defraud my customers on the first sale." 

"It's not for the next twenty-five to fifty days, it's for every freshman in my enclave."

"Neat, we have a deal. If you have any problems let me know, they've been tested plenty back home but Scholomance will Scholomance."  

"That it will."

He draws out the mana to pay for the potions.

He proffers his power sharer and pulls five vials from the tray. "Pleasure doing business with you. What's your enclave, by the way?" 

"Atlanta. Yours?"

Bella races back somewhat fuller. "I have to pay her back with interest but I'm going to call it worthwhile if these work and tell everybody in the school if they don't," she informs Alexius.

"Jacksonville." He can't call it a nonclave with the juniors watching, they'll get offended. He just thinks it. 

To Bella: "Interest, huh? Maybe I should take a leaf out of Suze's book and start a mana bank. And yeah, totally understand. I drank one this morning first thing, so if they don't work I'll be mighty surprised." He cheerily hands over a vial in exchange for six MH. 

"Say when, I'm not used to mana hours as a standard," she says, and she forks it over. "She just doesn't want me to get in the habit of leaning on her past the first week or so."

"That's because I just invented them. Somebody had to." He holds the glass bead in one hand while he proffers the power sharer with the other, makes a face like he's calculating, and after approximately six hours' worth of effort have poured through, "aaaand done. Sounds like Suze's on the right track, but I was being serious. If an enclave loans mana to someone they have a vested interest in their survival, see? Win-win." 

"I mean, I'm pretty sure Suze doesn't hate me and want me to die anyway, but I guess owing her mana can't hurt, sure."

"Oh no, I didn't mean it that way. Just that mentioning interest gave me a real idea. I meant the not-leaning-on-her bit was good, too." 

"Please do not become some kind of mana loan shark. Although I guess it wouldn't be that bad compared to financial loan sharking, since mana generation goes up over time?"

"You know, that was my next thought, how does one disincentivize loan sharking? Know any budding economists over in the...enclave whose name I never asked?" 

He sticks out a hand. "Alexius Marcus, by the way. Affinity: me." 

"Bella Swan, metamagic." Handshake. "I'm going to take intro econ after I eat - whiiiich I should do, but I might sit here?"