“Oh, them? They’re generally weak-minded—”
 
 “A group of mer who share the sea with us,” Tavish cuts in, his sharp Findlay voice tearing through his father’s words like a knife through melting butter. “Selkies haven’t been the kindest to them over the centuries. We reached a truce a few decades ago, and now they pay the Mara Diplomatic Assembly a heavy tax to continue living within the North Seas.”
 
 The thought makes my chest tight. “I’m feeling better and better about my life choices,” I grunt, wishing the assassin’s blade in my memories was a little closer to Raghnaid’s neck. The parasite tears the thought away, replaying the moment Lachlan mentioned the finfolk manuscript.I was getting there,I snap. But I take the hint. “What do those papers say?”
 
 “Yes, right,” Lachlan mutters. “A few decades ago, we analyzed records of aurora-host energy consumption and emission and concluded that the energy produced by ignits appears out of nowhere—it’s created. Such a startling revelation that it rewrote our very laws! Energy cannot be created or destroyed—except through the knitting of the auroras.” He flips through the pages without reading, turning each in a ritualistic rush. “But this finfolk claims that we shouldn’t be so quick to excuse the energy in ignits as created just because there’s no other easy explanation. They propose that our initial theory that energy cannot be created or destroyed is still true, and the energy auroras use for their ignits is being pulled from a secondary place.”
 
 My heart sinks. This is useless to me. But the creature still builds like pressure in the back of my mind, as though it’s trying to force some kind of knowledge into me.
 
 ‘Pulled from a secondary place,’it repeats, following it up with that same stupid sentence: ‘I get odder the more you know of me.’It slips deeper into my mind, nudging at the inside of my skull.
 
 I cringe away from its warmth, physically flinching right, then left.And you’re trying to drag me there, too? Trying to pull me into whatever the fuck is happening in Lachlan’s lab and your feelings toward those mutants the poachers were after? I won’t let you. You can’t have any more of me. I have my own problems and my own home, and I’m going back to them.
 
 ‘That sounds tough.’It shoves the words at me with such force that my jaw clenches in a combination of my own disgust and its unbridled determination.
 
 Yes, you are, I reply.
 
 At that, it fumes, its frustration sinking into my bones and making me itch to pace.‘I’m trying to save,’ it hisses.
 
 I know where that sentence was meant to lead—a softI’m trying to save youwhispered to my precious crocodilian Sheila when she was only a hatchling tangled in a fisher’s leftover netting. The wordyoucut off at the end means more than the rest of the phrase combined. This parasite isn’t trying to save me. It’s condemning me to save something else.
 
 “I received another paper by the same scientist earlier this week, but I haven’t gotten to it yet. So much science, so little time, you know. Could be useful though.” Lachlan tuts. “Oi, Sheona, fetch it for me! It’s in my suite, in the stack beside the rightmost desk. Should be titled something about dimensional theory and the motion of energy through space.”
 
 Sheona hesitates. The wrinkles around her eyes tighten.
 
 “We haven’t all day!” Lachlan snaps. “No one is paying you to ignore orders.”
 
 Tavish’s grip tightens on his cane, but he nods to Sheona.
 
 “Untwist your pants, I’m going.” She shoots Tavish a worried scowl as she steps out of the library.
 
 “The possibilities though—as I was saying—the possibilities of a secondary place from which ignits and auroras draw energy are endless. What we could do with that knowledge if we could uncover it!” As he speaks, he shuffles through another of his drawers, blinking rapidly and giving little shakes of his head like he’s trying to dislodge it from his body. “And you—you could be the first step! With proper lab equipment, we can compare your energy readings to those in the Trench. What happens when your energy is drained through exertion? Through lack of sleep or food? You produce no ignits; does this alter the amount of energy your aurora creates?”
 
 I fight the urge to look away from him. In the Murk, no one takes their eyes off a predator. I think the same is true with the exceedingly wealthy.
 
 But the longer I watch, the stronger my panic returns, opening a floodgate through which the parasite’s feelings rush, blending us back into one person. One person aghast and terrified and even more furious. One person who would tell Lachlan, ‘Yes, take me to the lab,’ if the words would only come through the lump in my throat. I need to go there, I need to help—
 
 Fuck off, I hiss, but it feels more like a plea. My fingers ache as if they need something to do in order to be mine. I tap them restlessly against my thighs and focus on my breathing, counting the pattern of blue and gold in the floor titles.
 
 It takes so much of my concentration that I almost miss Lachlan when he leans back toward me—toward the side of me not occupied by the parasite. Something pinches my neck. The parasite’s anger fixes to mine, but as we both lift a hand to swat him away, I can’t quite see the motion out of my periphery, my vision shrinking around the edges. My fingers bump numbly into something—my own neck? The parasite’s furious shrieking dims. My world turns on its side and snaps out.
 
 “Father, what was that?” Tavish’s voice sounds distant, echoing from outside my hazy burrow.
 
 “Oh, dear, seems he’s passed out!” Lachlan shuffles about, nearer but still a thousand miles away. “Better take him to the lab, yes, best—”
 
 “Passed out?”
 
 Something squeezes my upper arm and pokes the tender skin inside my elbow. I try to yell, or whisper, or even moan, but my lungs clamp up. The parasite struggles with me, fluttering around in my head. It burns at the fuzzy edges of the world, slowly bringing them back into focus—destroying whatever chemical Lachlan used to knock me out, I realize.
 
 “By the Trench, Father, what is happening?” Tavish shouts, clearer or closer, possibly both.
 
 “Ah, nothing, nothing. He seems stable. There’s a gurney in the lab, we can send for that.”
 
 I force my eyes open. Light floods in, and as the blinding whiteness clears, I find Tavish hovering a little way off. He cautiously nudges his cane toward me, his face ghostly pale. Lachlan kneels at my side, almost out of sight as he bends over my arm. When his gaze catches on mine, his own cheeks sallow to match his son’s, his throat bobbing. He moves faster.
 
 A rush of energy floods from the parasite, coursing through me.
 
 I yank away from Lachlan, struggling to pull myself to a sitting position. A needle pokes out of my inner arm, quickly filling a vial with my blood. The sight jolts me to a stop, a wave of wooziness crashing through me, not simply because of the blood taken without my consent, but because it doesn’tlooklike my blood anymore. Iridescent shimmers and soft, sparkling, white flecks glow through the dark-red liquid.