This branch of the Templars of the Ivory Labyrinth (these ones call themselves the Lords of the Maze) are not nearly stupid enough to leave her entirely unguarded, even at night. But they just pulled off a great plot, and the two who are supposed to be guarding her are very drunk and very preoccupied with their card game, and neither of them is actually paying especially close attention to their prisoner, or even particularly looking at her. 

(On guard duty tonight are Snare, the one who likes to call her a "diabolist whore," and Ruse, the one who was convinced that she must be holding back information about the operations of Fort 17 from sheer obstinacy rather than because she had never so much as passed through it on patrol.)

She counts the drinks going into them, and once the number is high enough for her liking, she shifts around her horrible little stall until the angle is right. Then she concentrates.

There's a first-circle wizard spell called Secluded Grimoire. It can be used by a wizard to hide their spellbook in the ethereal plane indefinitely, and recall it with a thought. 

Muvaki has never used it for this purpose, however, because she's not stupid. She can hide her spellbook without spending one of her precious spell slots on it. However, nothing was stopping her from using Secluded Grimoire on someone else's spellbook. 

She did this once or twice, as a mean-spirited prank, the victim's spellbook always turning up in a weird place.

Then, someone charmed her and talked her into stealing from one of their teachers for him. She'd been caught and gotten tortured, worse than she'd ever been tortured in her life.

So three weeks later, she snuck into his room, cast it on his spellbook, and kept it hidden away.

She realized on day two that it's still there, three years later. She can still recall it. And once she does, she'll have a spellbook.

The book appears in the corner of her cell. She shifts slightly, opening it.

 Reading out of the corner of her eyes, doing her best to monitor the ongoing card game, she begins to prepare spells.

"—Hey! I've got two sixes, you've got three sixes, that makes five!"

 "Yeah, because we shuffled two decks together."

"Fine. But after this game I'm counting them all, and if there's the wrong number you're going to get it, you understand me?"

 "Yeah, yeah, I got it. It's your turn, you have a card to play?"

In some ways, it's one the more agonizingly stressful hours of her life. 

In others, it's quite straightforward. She's playing a game, just like they are. The rules of the game are very simple. She has to prepare her spells without alerting them. If they win, they'll take her spellbook, and torture her until she dies, days or weeks or months or years from now. 

If she wins, she gets to kill them, or die trying.

"Two and two, I win! Pay up."

 Ruse hands over two copper.

"You trying to cheat me? You said you'd give me three if I won."

 "I said two. Count yourself lucky you're getting it at all, after that stunt you tried to pull with your queen."

She waits until Snare, the one with the keys to her cell, is busy looking at the hand he's just been dealt. She casts Sleep, aiming for Ruse.

 Ruse slumps over. 

Wow, he must have been drunker than he thought. Snare's going to take the opportunity to look at the top few cards of the deck before he wakes him up.

Charm Person.

She feels it land.

"Heeeey Snare~", she says, hating the tone of her voice but pressing on anyways. 

He grins at her. "Aww, you looking to have some fun tonight?"

She nods. "If you let me use my hands, I promise I'll make it worth your while."

"Maybe if you ask me really nicely."

"Pleeeeeease?" She flutters her eyes at him. (Ugh ugh ugh)

"Alright, little whore, but you'd better be grateful. I'm doing you a favor here."

He comes over to her cell, unlocks it (it takes him a couple tries to get the key in properly), and steps inside.

She holds up her shackled hands for him, eyes big. (His knife is on his belt. Just a few more steps. All she has to do is not puke.)

He unlocks them too. "Now, what do we say?"

"Thaaaank youuuu," she says, and pulls herself up against him, putting one arm around his back - "mmmmmm" - and reaching carefully for his knife.

She can get it! He's rather distracted at the moment!

Well, he'll probably figure it out when she stabs him in the neck with it.

Twice, for good measure.

He collapses to the floor of her cell.

She makes sure his blood doesn't get on her stolen spellbook, then steps over the body to go slit Ruse's throat before he wakes up. 

In theory he's the stronger fighter of the two guards, but that doesn't do much to protect against having his throat slit. Now he's dead too.

She sobs in relief, shaking.

But she's not done. They have a wizard and three more swordsmen. And she's going to kill all of them for doing this to her.