In unison, the cats blinked. Then they all stared at each other with undisguised hostility, regretting their moment of uncharacteristic vulnerability.
"Forgive me," said Assassin. "I am accustomed to keeping my secrets and playing my games. I am somewhat unprepared for dealing with an honest soul - no doubt you understand. So firstly, my confession: My objective here is an unfortunately small vanity. You see, in my life there was a beautiful language called French, the language of love and nobility, spoken in all the courts of the world. Eventually the centers of power shifted to foreign courts. Language evolved and mutated. And with it went knowledge of how to pronounce my name. Over the course of aeons some truly abominable permutations have come into being, and my wish upon the Grail was for a small correction to restore my language to its exalted place."
It is strange to see a collection of cats laugh. The motion is a flurry of scrambling and pouncing and diving, a whirl of mirth. "Petty, yes? But all of the Servants here came for wishes as ridiculous as this - desires to be remembered on different terms. Only Caster - and I through eavesdropping and preparedness - knew the truth of the Vault."
The cats, exhausted by this outburst of play, settled themselves into perches of rest, the outline of a comfortable chair in half a dozen snoozing tails and fluffy loafs. "In the dying days of the Burrower empire, after the death of the nine suns and the exodus of the settlers, God sent a falling star to the Earth. It was a diseased thing, thick with alien life that viciously grew in the form of a terrible forest atop the desert wasteland. For many weeks the Nineshard Princess fought the jungle to a standstill as her companion descended into the underworld to find the last remaining Lord of Hell. Through song and love, she touched the Demon Queen's frozen heart and earned her aid.
"The Demon Queen used the power of the Sunshards to release nine powerful ghosts from her artificial Hell, what she called the Penitence Loop. The Loop was a ghastly device, a machine that harvested the energies of souls within it rising and falling in a simulated environment, a - what is the modern term? A 'Do Not Create The Torment Nexus' situation, only this one inspired by Eastern religious texts. The Karma Turbine.
"Together they defeated the fallen star and sealed it in the Demon Queen's deepest palace, bound by the Loop and overseen by two Servants set aside for the purpose. To watch over the Star and the Loop, the Queen bound the Demon of Righteousness, Adam, whose personal morality would never allow him to falter in his diligent oversight of his charges. A perfect, self-reinforcing bubble. But then, when you and your friends cast your spell and contact with the outside world was forced upon him, he was entirely free to flatter and corrupt vulnerable souls. The wish is bait. It is achievable with the controlled detonation of the Penitence Loop and its phenomenal accumulated mana supply, and is therefore an honest offer - but the side effect will be the release of the Star to resume its wicked work.
"I sought to kill Saber via Rider early because I knew she would be a particularly deadly blade in his hands - though neither he nor I foresaw her transformation into Avenger. Lancer was a second choice for weapon, and one far less threatening than Saber would have been. I would have been just as vulnerable to his manipulation had I not the forethought to send letters to myself during my last incarnation.
"As to where Adam stands now, with Caster's aid he has begun the process of overclocking the Penitence Loop - accelerating it with mana harvested from defeated Servants so that it will begin to overload and break down. The power of the Star is leaking - you saw it in the underground jungle - and Lancer is absorbing that strength. Sooner or later the seal will crack and the fallen Star - along with all the souls trapped inside the Loop - will erupt onto the surface. It will be a calamity. Caster, in despair, imagined this to be a good thing.
"Perhaps Lancer too might listen to reason," he finished. "But the issue is that I cannot think of a way to talk to her without her killing me before I finish speaking. She is terribly powerful as she is now, and has Adam by her side to explain away or intercept any letters I might try to send her. But nor can we delay too long, lest Lancer's might blossom such that she can fight the two guardian Servants outside of the Demon Queen's mansion directly. I can, of course, carry a letter to Saber - wounded as she is, I believe her to be safely beneath Adam's notice."