Morty knows he shouldn't be screwing around with multidimensional shit. It's dangerous, it's impractical, it's blah blah blah. But it's a potential key to unlimited energy, how does nobody see that? He's built a dimensional siphon (it kind of looks like a cardboard box with a funnel and a TI-84 taped to it, but it damn well works), keyed in the dimensional coordinates to a random plane, and by God he's going to use it.
He flips the switch and waits for the energy bar to fill up.
It does! It fills up very rapidly. Then it explodes, along with the box. There's rather more smoke than there should be, and once the smoke clears someone is standing there.
"Oh dear," Morty says faintly.
"Okay, so I'm gonna have to do some stuff so walking into this thing doesn't just bonk your nose." Ariel closes her eyes and starts fiddling with the air.
Abruptly, there is a short Greek woman with large quantities of hair and an irritated expression standing in the hallway. "As I've told you before, I spent a very long time designing that passageway, and I'll thank you not to muck with it. Flicker, it is good to meet you. Please, come in. Without destroying the door."
Ariel looks cheerfully unrepentant as she follows her through the wall.
"Circe, would it offend you if I told you that I like your office door better than you?"
"It would be very reassuring, in fact. I encourage you to continue feeling this way."
"Yes. Congratulations. I will meet with you on Sunday of each week, apart from the week of Christmas in your world, which you will be spending away. There will be no excuses unless you have died or are otherwise physically prevented from coming to my office. If you have contracted the Mongolian Death Flu, I will provide you with a wastebasket into which you may vomit while I instruct you. This is a part of your education, and has been the case for every student I have educated since the ninth century BC. Is this understood?"
"If I get the Mongolian Death Flu - is that a real thing? - perhaps it would be more efficient to send me home briefly, or summon one of my sister, so that she can fix the problem before we proceed."
"The Mongolian Death Flu is a term that I have unfortunately picked up from your companion for any highly unpleasant but nonfatal disease. Fatal diseases should be treated by a healer. Healing nonfatal diseases by our methods will weaken your immune system, healing them by yours would cost exorbitant amounts of money, and working through them is a learning opportunity."
"I am much more interested in learning magic than in learning about the unfortunate throes of the Mongolian Death Flu. Can I get a loose ballpark on how exorbitant these amounts of money would be?"
"By 'a learning opportunity' I mean that if you can concentrate while you are going through physical discomfort you will become much better at concentration in general, and concentration is paramount to all magic. A single round-trip summoning and banishment spell today would consume $8,000 worth of powdered mithril. Depending on how the selected date aligns with various astrological events, that cost might be lessened by up to $5,000 or raised by up to $15,000. One of your first assignments will likely be to work out a calendar of when the best and worst dates would be and why."
"If it is legitimately worthwhile for me to practice magic while physically uncomfortable I will do it while hanging upside down. I suspect that arbitrage alone will enable me to treat five to fifteen thousand dollars as a very reasonable price to see my sister and incidentally cease to suffer the Mongolian Death Flu."
Circe rolls her eyes. "I was not going to go into this until somewhat later in the meeting, but your logic is solid and you are unusually persistent, so very well. An important part of this arrangement is going to be moderating the implicit Sorcerer's Contract inherent to an apprenticehood-style relationship. Essentially, the fact that I will be personally educating you means that mystically speaking, you will owe me a substantial debt. This can be dealt with by various means, including a term of servitude or a simple payment in Essence, but if I concede too much to making you comfortable then the terms of the agreement must become accordingly steeper. I do not intend to be deliberately unpleasant to you, but there are certain clauses of my arrangement that I am loath to alter because they have a practical purpose, they helped me to become the sorceress I am today, and they keep my rates down. And before you ask, no, you will not be able to pay in coin. Magic stubbornly refuses to acknowledge fiat currency, and base metals and gemstones, while valid, are valued at an irritatingly low rate of exchange. You would need multiple tons of pure gold to satisfy the debt of the current arrangement, let alone a softened one."
"That is very interesting. Certainly it removes any objection I might have had to turning up to lessons with a broken leg and a concussion. I retain my problem with contagious illnesses and propose that you give me simply astronomical amounts of homework or something to compensate. I also want to know what you're planning to charge if it is not in fact multiple tons of pure gold."
Perched atop a bookshelf, Ariel cackles obnoxiously at the idea of anyone saving Circe's life. Circe spares her a dirty look.
"What is the content of 'could not refuse', exactly? I do not wish to rip you off, I just wish to be - circumspect."
"I would not be able to discuss the tasks with you beforehand, as that would put you in a position of power, but I can get the parameters of what you would find acceptable, such as 'nothing that could put me in substantial physical danger'. If you refused me, any Essence you had collected or would ever collect again would curdle, and you would have horrible luck for the rest of your life. Of course, that's the effect of intentionally breaking the contract in any event, or any oath of a similar level. I have three thousand years' practice at predicting tasks an apprentice would find acceptable, but I understand if you would rather choose a lower-risk option."
"That's not quite what I was asking. Suppose for some perhaps wildly improbable reason we wind up with a task on the table that is not acceptable. Do I carry it out against my will like a marionette? Do I write around in unspeakable agony until I do it? Does trying to refuse instantly kill me? Do I spend the period of time in which tasks are issued unable to perform cognitive tasks as complex as 'evaluate acceptability of things'?"
"You would be allowed to refuse, which would result in your Essence curdling. Which is an unpleasant but usually nonfatal experience. I meant 'unable to refuse' in the sense of 'without breaking the contract'; I apologize for any confusion."
"And at this time, hopefully without giving offense, I would like to know how hard it is to self-teach this kind of thing."
"Genuinely offending me is difficult verging on impossible, as is self-teaching magic. You could also simply enroll in the Mystic Arts program, which would teach you how to be profoundly mediocre at magic, whereas my tutelage would allow you to eventually rival my own considerable power and become immortal. I would like to add that the Essence-payment option can also be paid in smaller installments, or simply saved up bit by bit over an extensive magical career. I will be around for a very long time; I am in no hurry."
Bella smiles slowly at "immortal".
"And Essence is a renewable resource if it's parceled out responsibly, it's like the more useful equivalent of fingernail clippings or whatever?"
"But teacher, didn't you say magic has no concept of interest?" Ariel calls from the ceiling.
Circe pinches the bridge of her nose. "I will mix my metaphors when I choose, Stormhammer."
"So that definitely sounds like the most - predictable - method of repayment. I am also curious - principally on a conceptual rather than a system-gaming level - why exactly tutoring forms a debt that needs to be handled or else the magic 'curdles' at all. Learning other things does not have this property."
"Magic has a certain- sense of what is appropriate. Giving something away without receiving something from the recipient in return offends it. However, it does not involve itself in every child's arithmetic lessons, because it has not been invited there. Tutoring you in magic is, obviously, a magic-intensive process. Thus, it establishes a certain expectation of the magic that is left behind, the magic that you now possess. If it is not appeased with an appropriate payment, the magical assistance I have given you becomes a gift, and magic abhors a gift. The same applies if someone saves your life. As a mage, you must genuinely intend to return the favor in one form or another, or your luck will sour for the rest of your days. Fortunately, in that case you have the advantage that intent is all that matters; as long as you resolve that you would save their life given the opportunity, and make good on it if that occurs, you're in the clear."
"Why does magic abhor a gift, and is this going to interfere with my ability to perform unreciprocated good deeds?"
Ariel chimes in from her hover, "Oh, yeah, and if I end up giving you that intellect circlet thing for Christmas you don't have to worry about precise values, just give me a gift in return. The conceptual nature of Christmas loosens the rules a bit."
"Intellect circlet?" Circe raises an eyebrow.
"Yeah, is that a thing I can do?"
"You, not a chance. Sally, perhaps, given three years, half a pound of mixed corundum, a pound of mithril, and six ounces of orichalcum."
"So... probably not for Christmas."
"It would be a bit of an investment."