And if Magnus was still in there casting defensive spells instead of running the hell away, that meant that one of the mals was keeping at least the New York corner and therefore also a heap of other kids from getting out. It was the most perfect gift-wrapped opportunity to show off that I could possibly have asked for. The main aisle was even lit the whole way down to the reading room like an airport runway.

I didn’t charge down the aisle and throw myself into the beautifully visible fray. I’d been a little slow on the uptake about the book, but I’m never that slow. The library had wanted to keep me in the Sanskrit aisle, but now it wanted me in the reading room. That meant it wasn’t trying to stop me saving Orion. It just didn’t want me in this aisle. And it wanted me out of here so badly, it was even holding out everything I’d been sitting in the nook dreaming about, wanting.

So I stopped instead, right there in the corridor, and then I turned around and looked into the dark behind me.

The library air vents are in the aisles, old tarnished brass gratings set in the floor. Their edges catch the light when you’re walking in the library, thin gleaming lines reflecting even when the lights are dim. I couldn’t see the one that should have been behind me. I couldn’t hear the annoying grate of the old grimy fans, or even the omnipresent rustle and scrape of pages shifting: as if even the books on the shelves had gone still, like sparrows when a hawk is circling. The background noise wasn’t just being drowned out by the noise of the fighting behind me. I held my own breath to listen, and I heard faintly the sound of many other people breathing, soft and dark and heavy. The lights overhead were out completely, but Orion’s next spell-burst was coming, another flash of light. My whole body was clenched and waiting for it, and in the next flare of deep-red light I met half a dozen human eyes watching me, scattered over the thick rolling folds of the translucent, glossy mass that was just bulging its way out of the vent, many mouths open and working for air.

Because I usually have to sit in the front rows of Maleficaria Studies, I have an especially good view of the graduation day mural centerpiece, featuring the two gigantic maw-mouths who have pride of place on either side of the gates. They’re the only mals that have names: ages ago some New York enclavers started calling them Patience and Fortitude, and it stuck. They remain purely decorative, though; we don’t study maw-mouths in here. There’s no point. There isn’t any way to stop a maw-mouth killing you. If you get out the gates quickly enough, they don’t get you. Or if something else kills you first. That’s the only practical advice the textbook offered about them: if you’ve got a choice, take the something else. But once they’ve got you, even a little curl of a tentacle around your ankle, you’re not getting away. Not on your own.

The flaring light of Orion’s spell went out behind me, and I stood there staring into the blind darkness until the next one came, a long firecracker burst of bright greens and blues. The maw-mouth was still there. It blinked back at me with some of its borrowed eyes: brown eyes in a lot of shades and shapes, occasional blue eyes and green eyes, gliding gently in opposite directions or alongside each other over the surface as it kept flowing up and out of the vent, some of them getting buried and others rolling out into the light, pupils contracting in the brightness. Some of them had wide staring expressions, others blinked rapidly, others looked glazed and dull. The half page on maw-mouths in the sophomore-year textbook also informed us in clinical prose that no one is certain what happens to those consumed by maw-mouths, and there is a substantial school of thought that believes their consciousness never actually ends and they just get exhausted into silence. For further reading, see the seminal literature by Abernathy, Kordin, and Li in the Journal of Maleficaria Studies, who discovered that it was possible to direct a communications spell to even a long-digested maw-mouth victim and receive back a response, albeit nothing but incoherent screaming.

I made Mum tell me how Dad died when I was nine. She didn’t want to. Before then, she just said, “I’m sorry, love, I can’t. I can’t talk about it.” But the morning after the scratcher, sitting huddled in bed with my arms around my already knobbly knees, staring at the streaked-metal walkway made out of the first hungry thing that had come out of the dark for me, I said, “Don’t tell me you can’t talk about it. I want to know.” So Mum told me, and then she spent the rest of the day crying, in deep gulps, while she went round doing her rituals and putting things away and cooking, barefoot the way she almost always was. I could see the ring of tiny pockmarked scars around her ankle, the familiar ring. I’d liked it before; it fascinated me. I’d always try to touch it when I saw it when I was little, and I’d asked Mum about it a lot more often than I asked her about what happened to Dad. She’d always pushed off that question, too, but I hadn’t realized it was the same question.

The one and only way to stop a maw-mouth is to give it indigestion. If you rush into the maw-mouth on your own, with a powerful enough shield, then you have a chance to get inside before it can start eating you. In theory, if you manage to reach the core, you can burst it apart from there. But mostly people don’t get that far; there’re only three known cases where that’s ever been done, and by a circle of wizards. The only realistic goal for a single wizard is to distract it. That’s all Dad did. He grabbed the tentacle and pulled it away from Mum, back into the mass of the maw-mouth. He had time to turn around and tell her he loved her and loved me, the baby they’d only just realized was on the way, and then the maw-mouth got through his shield and swallowed him up.

Maybe it had even been this one. I knew it hadn’t been Patience or Fortitude. Those two are so big, they don’t move around anymore at all, and they rarely eat students except by accident. They spend graduation day eating up any other maw-mouths that unwarily come in reach of their tentacles, and the biggest other maleficaria. This one was clearly more energetic. There’s never been a maw-mouth in the actual halls of the school before. As far as I know, of course, but they’re not the kind of maleficaria where nobody escapes to tell the tale. You have lots of warning from the people screaming and thrashing as they’re being swallowed. But the ones in the school have always been happy to wait down below for the annual feast.

The next flare came from the reading room as the maw-mouth finished pulling the last bit of itself out of the vent, the mass briefly keeping the boxy shape it had been squashed into, before it softened back into blob. It just sat there, its silent mouths working, taking long deep breaths, as if it was recovering from the massive effort of getting up here to hunt. I didn’t run; I didn’t need to. Even small maw-mouths don’t eat one at a time. If it gobbled me up, it would have to sit here digesting before it moved again, and in the meantime everyone else would clear out. That was why the library had been trying to keep me away: so I wouldn’t give a warning. It wanted to give the maw-mouth a good sporting chance to eat not just Orion, but everyone in the reading room. Not to mention those four powerful maleficaria that had probably come up here running away from the maw-mouth in the first place.