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.
"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."
"Alas. I'll have to save up for ingredients and curry favor with your roommate. How does essence work overall, is it like - mana in a video game, or what?"
Circe creates a diagram in the air, a glowing ball of magic that she pinches bits off of until it dissipates completely. "To retain your Essence you must constantly be vigilant and guard your thoughts from waste. Passing spite and unspoken wishes - 'I wish I looked like that,' 'he should be with me,' 'can't she stop talking for a moment,' - pull from your Essence in a futile attempt to make themselves true. A mage does not wish. A mage does, or does not. There are other ways to casually lose Essence, by gambling or by drinking to excess or even in your dreams, but the former two can be consciously avoided and the latter will happen less and less as you gain discipline."
She sits back down. "Thus, for your first few weeks we will be working on meditation exercises to prevent idly wasting your Essence through your thoughts. You will also begin on the magical theory curriculum, but until your thoughts are perfectly under your own control any attempt at practical magic will be futile."
"Oh, this is going to be fun. I assume it is still possible to form - passive preferences? Non-wastefully?"
"Yes. As long as you do not attach too much weight to your thoughts, you may think what you like. I thought you might enjoy this part. You seem the type to enjoy absolute control over yourself."
"Immensely. I'm good at it, too, although admittedly not the kind of good at it that I imagine I'll be able to finagle when there's concrete results other than my personal satisfaction attached."
"Practice never hurts. I was not so good at controlling my feelings when my education began, and while I overcame it, I'm sure you'll have a better time all around. And the more quickly you can hold on to Essence, the sooner you can accrue enough to ignite properly. Then, your education begins in truth."
"And you see no reason why my being from another world should interfere at all with accumulating, igniting, and using Essence in a locally conventional fashion."
"If that were the case, I would have taken one look at you and shaken my head and expressed my deepest apologies. I have not done that."
"Good, good. I do not currently know what day of the week it is here...?"
"Tuesday. However, if you wish, we may as well have our first meditative exercise today. I have nothing scheduled for a few hours."
"I... will take you up on that after fifteen minutes to deliver a more complete explanation to my sister of my plans so that she can explain to our parents, because apparently they're freaking out and I still haven't told her why I even wanted the price of silver."
"Naturally." Circe sits on a large leather couch, looking exactly as comfortable as always.
And she stops doing the chin-on-hand gesture that seems to be her convention for indicating when she's talking to her twin.