Luna didn't come back for a while, and I'd had a long day, so I decided to get some sleep. I wasn't able to talk, but with a bit of hoof-pointing, pantomime, and in one case, just grabbing an amused guard's armour and dragging him into place, I was able to create enough of a 'herd' next to my cushion so that I actually could fall asleep.
I was woken up while the moon was close to the opposite horizon. The guards were extremely polite, but also insistent that I go with them. Even if I was able to resist them, I didn't have anyplace better to go at the moment, so I allowed myself to be led. Eventually, we made it into the basement, and arrived at a door that seemed no more interesting than any other door, and I was ushered within.
Plain the stone walls, bright the magical lights, glorious the two equine divinities. Once the door was closed, both their horns glowed, and they swept various magical energies across the walls, ceiling, floor, each other, and myself. Finally, they seemed satisfied, and Celestia nodded. "We should be able to talk reasonably freely," she told me, "without fear of being overheard."
"Mooooo?" I lowed.
Luna looked abashed, and her horn glowed for a moment, as did my tongue. I wiggled it a bit, then hazarded, "Myyes?". Not quite as clearly enunciated as I usually managed, but it was still speech.
Luna's brief embarrassment turned into a glower. "We are going to talk, now. Thou arrivest without a past, with strange knowledge, and a claim of insanity - and when presented with a tool, thy first thoughts are the use of code books and secrecy. Who art thou?"
My ears had flattened at the onslaught of the Royal Canterlot Voice. I saw a brief twinkle in the Sun Princess's eye - it seemed that Trollestia was still avoiding telling Luna that the R.C.V. was centuries out of fashion. Luna seemed annoyed with me, and telling her would likely make her moreso, so I didn't have anything to gain by mentioning the topic at this point. So I simply cleared my throat, and replied, "Your own lunar magic should have told you that I have been completely honest with you."
"Yes - but thou art keeping secrets from us!"
"Of course I am."
My agreement seemed to briefly derail her line of questioning, and Celestia stepped into the silence.
"Why?" she asked, calmly.
"Because I think it's in all our best interests to."
That seemed to give both of them pause. This deep underground, Luna's moon wasn't shining down on us, so I didn't know if she was still using her truth-sense on me - but even if that wasn't the means, it seemed very likely that the two of them would be using something with a similar effect.
Celestia finally spoke up, "We are the Princesses of Equestria. It is not your decision to make whether we should know something."
I snorted - a lot more impressively than I was used to. "Of course it is. I take responsibility for my own choices, and my own actions - and my own inactions - in all senses of the word."
"Then we seem to be at something of an impasse."
"Of course we're not. I'm sure you have all sorts of ways to get me to talk, if you wanted to use them."
Celestia's eyes gleamed as she said, "I suppose we could go next door, to where I keep all my torture equipment."
I gave another snort. "If you're the sort of monarch who would use torture, then it's even more important that I not tell you. Besides, even without all the ethical problems with that - there's the simple fact that torturing people for information just plumb doesn't work. The poor people who have to suffer such things will say anything to get the pain to stop, and the only way to confirm anything they say is by checking other sources - and if you've got access to those other sources, then you didn't need to use torture in the first place."
The two of them were looking at me oddly again. Luna said to Celestia, in what passed for a conversational tone, "She has thou there, sister." And then, in an actual whisper, "And is not next door where thou keepest thy 'exercising' equipment?"
Celestia scuffed one of her hooves on the floor and coughed. Then she focused back on me. "I find it... disturbing that you seem to be so well acquainted with how useful torture is."
I sighed. "If you're looking at it that way - you're probably going to become more disturbed before you become less."
She tilted her head, then offered, "I could offer you a million bits for your knowledge."
I blinked, and seriously considered that for a moment. "Assuming that we could work out the practical details... nnnno, I don't think that would be best. I don't think even that amount of mere cash would suffice to get me what I want - and if it can't do that, then it would probably be more useful directed to your various government expenses. Besides, if I accepted, you could offer me five bits, and we'd just be haggling."
Celestia tried another tack. "If you are truly trying to act in our best interests, then would you be willing to swear a personal oath of fealty to myself and my sister, to do as we command?"
I winced at that. I turned to Luna, and said, "Please forgive me this response, but - would it have been a good idea for me to swear such an oath to you, a thousand and one years ago?"
Luna looked pained, and looked away from us both, which was answer enough; and I gave the rest of my attention back to Celestia. "I am willing to swear an oath to abide by the ethical principles I believe in - and I already have. I could swear an oath to abide by principles I don't believe in... but since I don't believe in them, I would be swearing to do what I thought was evil - and I won't do that."
"You do realize that you are being a most frustrating cow, do you not?"
"There are worse things than a frustrated Princess."
"Then perhaps I should ask - under what circumstances would you tell us all that you know?"
I remained silent, thinking about the problem. Luna had recovered her composure, and was looking back at me... and that jogged my memory. "That depends on something I don't know. If I were to tell you, and you agreed that it would be better if I hadn't... is there some way to grant such a wish? Some sort of spell to erase a memory?"
Luna spoke up, "There are several such, of varying sorts. Some to cause permanent forgetfulness, some to cause it for a time, some to cause it until some exotic phrase calls the thought to be recalled once more."
I nodded. "Then if you are willing to promise to use such spells, on yourselves or each other or however it works, I would be willing to tell you much more than I am right now."
Celestia smiled. "That is a very fair condition, and I am quite willing to do so."
The two of them so promised, in a formal but private fashion I myself promised not to spread beyond them if I could help it.
I muttered to myself, "I should have taken the million bits, too," gaining a smile from them both, then started out, "If my memory is correct - and at this point, I believe it is - then as of a couple of days ago, I had been a male all my life..."
A number of hours later - interrupted mainly by their need to raise the sun and lower the moon on schedule - I had finished telling what I felt best to tell, conclusions had been drawn, a plan created... and the two Princesses fulfilled their promise, and wiped their own memories of nearly everything that we had said. They wrote notes to themselves about what they'd decided should happen next.
I walked out of that basement a free heifer - of sorts. I was now officially a government employee, tasked with finding better and more efficient ways to preserve foods, so that surpluses could be better stored in case of famines or other disaster. I was given some lab space in the palace's basement, and had an excuse to wander through Equestria to chase after unusual reports.
(As it happened, I actually knew of at least one such food-preservation method not in use in Equestria - though it would probably be a bad idea to actually pursue it. Irradiating food killed all pathogens, allowing sealed foods to be stored nearly indefinitely, didn't seriously degrade nutrients, and didn't actually make the food radioactive - but also required knowledge of radiation, and I was pretty sure that I didn't want to share Marie Curie's fate.)
If somebody thought I was being too much of a goody-goody, I could reluctantly admit that I had a more personal reason for the job - in addition to landing a big government contract, I was hoping to make an obscene amount of money by applying what I found commercially, as well. But that was just a minor secret. A bigger one was that the food-preservation job was mainly a cover; and that the real truth was that I was actually likely a traumatized, mildly insane survivor of a herd-abduction, and my real government job was looking into any such enslavements of Equestrian cattle - and of ponies, and of other creatures.
And that secret was, itself, hiding a deeper secret: one that the Princesses themselves had made themselves forget for at least weeks at a time. And this was that I had convinced them that it was worthwhile to search for some ethical means of achieving immortality, for myself and for their little ponies, if such could be found; and that even the search for that was best done quietly and secretly, in case other beings caught wind of it and tried engaging in a similar search but without the ethical constraints.
But all those stories, while containing at least a kernel of truth, were hiding the deepest truth of all: that my arrival in Equestria was not the result of some accident of nature, some lightning-bolt out of the blue that had sent me tumbling across worlds; but was, it seemed, the deliberate act of some powerful being... a being whose identity, location, powers, and motives were completely opaque, and who was capable of doing at least one magical feat beyond even the Princesses themselves. And it was a truism that there was very rarely 'one' of anything in the universe, so if one such being existed, there might be others - and letting any one of them gain even a hint that we had any idea that any of them existed could result in much more severe consequences than a mere memory-charm.
And so the Princesses arranged their memories so that they would have no recollection at all of them, so that there would be no change in their behavior should they be watched by any such beings, and that memory charm was itself hidden inside the shallower memory charm about the search for immortality, which was disguised by my job as an slavery investigator, which was disguised by my interest in personal profit, which was disguised by my job as a food preservation researcher...
... and, at all levels of that, I was still going to need help from others. If for nothing else, to have somepony to lie down next to when I needed to sleep. I wondered if I could get Micro Scope assigned to me on a more permanent basis; her interest in small things might be useful in checking to see if any given form of pasteurization really had killed all the bacteria... and perhaps she might become trustworthy enough to join in one or even two layers of the deeper plot...
... though after her involuntary haircut from the windmill the other day, she might be as likely to buck my snout in as give me the time of day. Ah well - there was a risk in everything, and maybe I could butter her up with some butter, or custom ice cream, or some other dairy product...