Hm?
Oh, you must be new. I imagine you've been told to ask me about someth-
Ah. Yes. 'Forbidden knowledge'. A familiar topic, and one about which I know a great deal. I know a great deal about a lot of things — I'm the archivist of this place, after all — but this one… well. You might consider me something of an authority.
In the Library, strictly speaking, there is no forbidden knowledge. Every book, every text, every word, is available for a willing patron to peruse. There are restrictions, of course, but they are mostly there for the patron's own good, and a justified curiosity will almost never be restricted entirely.
Maybe you have found yourself hungering after some dark and ancient art, or an idea so dangerous it has a life of its own. Maybe you want to know the fate of someone excised from history, or summon a God long forgotten. These things are all, technically, allowed.
Technically.
The Library has a responsibility to protect itself, the knowledge it contains, and those who wander its hallowed halls. There are restrictions in place, dangers. Certain things are hidden from everyone's eyes, or blocked behind deterrents so harsh that even they're restricted beyond text.
But the thirst for knowledge is eternal, and there are always those who desire more.
Maybe you're one of them. Let's say, for the sake of argument, that you are. Or you were, rather. We'll get to that later. And maybe you wanted to know something which people won't talk about. You consulted other patrons and they just stared at you blankly, or maybe didn't hear you at all. You talked to archivists and they shuddered, briefly, before turning back to their work. Those docents that you could persuade to hear your queries shrieked and disappeared, and you never saw them approach you again.
So, of course, you began seeking more dangerous avenues. Maybe, like me, you scoured the text-mills of the MACROFICHE, where books too powerful to be bound are kept word-by-word on steel plates hundreds of metres across, swung into place by cranes the size of cities. The engineers are helpful, and they make good conversation, but none know of what you seek. And there's one too many missing limbs — maybe one too many disappearances — for you to be quite comfortable in their company. One day, perhaps, you saw someone chewed up by a gear the size of a building, moving too fast to see. And then the next day you saw them at their post again, skin pink and shiny. Oddly wet. They looked at you and smiled blankly, and you left too fast to pack your bags.
Or maybe, maybe you found the basalt caverns full of words of fire, written by deities and shipped to the library at great expense. You wandered for days, deeper into its midst, choked and burned and desperate, before emerging in a cloud of smoke from a trapdoor in the ceiling of an unremarkable reading room. Its occupants regarded you strangely for a moment before returning to their books. Stranger things than this are a regular occurrence, after all. You tried to turn back, but the trapdoor was gone, a thin charcoal marking all that remained. And it seemed to you that even gods wouldn't tell you what you want to know.
And maybe, then, with an all-renewed sense of determination, you redoubled your efforts. You began to chart the halls, find the places less trodden, and probe them for secrets. You pried open the doors of long-abandoned conference halls, hired exploratory teams to forage through the great fog-wrapped estates of dukes and duchesses passed. Navigating Asphodel, charting Eden… Hell, maybe you even found the Last Bastion of Reason, where infinity diverges beyond comprehension. You're still standing here, so I doubt it, but who knows. Maybe, maybe you found a way.
But even if you had, it wouldn't have been the way you wanted, would it? It wouldn't have been the answer whose question drove you mad over countless sleepless nights. The same knowledge that, possibly, tempted you to delve into… metafiction? Many men have done it, and some even kept themselves mostly sane — in this half-mad fervour, who knows what you would have been capable of. Maybe you'd have spent nights scaling cliff notes, plumbing the depths of plot holes, or exploiting the rule of threes. Seeking your quest's end within books within tomes within catalogues featured briefly in chapters of novels unwritten. Maybe…
…No. No, even I can't pretend that's what happened. That wouldn't make sense. People who break fourth walls like that… they do find their way here, but it tends to be as characters. Fictions, shades, plot points. You're solid, and real. Beautifully so, if I do say so myself. Delectably actual.
So, if not that, maybe… maybe you went mad, but with loss rather than desire. Perhaps, ooh, perhaps you sought solace in a lover's arms, pouring your heart and soul into theirs. Maybe your unbounded longing, turned potent by exposure to the Stacks, drove them to suiscribe, and you discovered their bloated corpse one morning crammed full of autobiography. And realising this, you weaponised your loss, targeting those with expertise and wringing every last semicolon from their lifetime's subconscious. You became a dark, twisted lover, a trail of bloody conquests in your wake. You tore people's hearts from their chests and devoured them in your thirst, a vampire of the mind.
Well, 'nonsense' is subjective. Some would say a man can't live without his lungs, but here I am anyway!
Alright, alright. Okay. I understand that you're confused, but-
Please, just calm down, I-
I'm trying-
Please! I'm trying to let you choose!
…A story, of course. What else? You'll need something to hold onto, now you've found your way down here.
Well of course, you…
Uh…
…You really don't understand, do you?
Alright, how do I put this delicately…
…Okay. How about this. When you entered, through the gate, you saw the skull, yes? And in the skull, the city of bones, carved from the skeleton of the Second Serpent? Yes, yes, I thought so. And someone in the city directed you to the hall, where you found me? Good, good. And you didn't stray into the mists outside? Wonderful.
My point is, try and remember what happened before that.
…Go on. Any detail, no matter how slight. Anything at all.
…Mhm.
Exactly.
You're welcome to continue your quest, of course. That, at least, should persist, since the goal was down here to begin with. We don't know how it happens, the crossover, but it does, and it almost always ends this way.
Well, if you head out into the shelves, you might find one that's not bare, and it might have something of interest. But remember, if you do, there's no coming back. This city is the last light before oblivion; after this, there's nothing.
The shapes? What shapes?
Oh. Them. Docents, I'm afraid. Don't try to talk to them, their lanterns are broken and they're little more than feral pests at this point. They fall through the cracks in the Library proper, sometimes, and wind up here. Blind as bats, poor things. Keen sense of smell, though. And exceptionally sharp teeth. As I said, try not to engage.
Well, you should be able to work that out. This is the underbelly of the Library. Books burned, stories lost… they all end up down here eventually. It's a cellar, of sorts. Or a dungeon. Nobody's ever found any kind of ceiling, or outer walls — there's the remnants of cities, no doubt scoured from the history books, but they're all abandoned. Nothing alive. Just miles and miles of ash, and charcoal-grey skies, and empty shelves.
Oh, of course, of course there's books. They're just few and far between. But they amass, slowly, as people are 'disappeared' from their various worlds. Once a text is destroyed everywhere, and exists nowhere — even in people's heads — it exists here. Forever. It's just the way things are. Everything has to persist somewhere, apparently, and dead memes are no exception.
This, my boy, is the Memocide. It's where knowledge comes to die. And I'm afraid… well, I'm afraid your story is over, now.
You're stuck down here with us.