The lake was so cold it registered as pain. Sirius might have been screaming if the cold hadn’t sucked all the thought from his mind. As it was, he thrashed in the water, hissing for breath, and trying to keep his joints moving. He was trying to come up with some sort of plan, but all he could think about besides how miserably, mortally cold he felt was to wonder how his teeth could be chattering when they were so tightly clenched. Focus, he told himself.
Lorelei still hung suspended in the air over the water. She was an unnerving sight hanging there like a wet marionette. Her wand was still clenched in one white hand. If only she had dropped it on the way, he thought unhappily. I could’ve taken it then and flown out here. I’d be warm and dry. I would be able to feel the rest of my body! He was tempted to become Padfoot in the hopes that fur would be more resistant to the cold, but needed hands to wrestle the wand from Lorelei’s grip. He had to tread water underneath her to get it. He couldn’t tell if she was breathing or not, but her fingers closed tight again after he pulled the wand away, so he decided she was alive.
Now he had a wand, but still no plan. The water was black as frigid ink around him. He looked down, hoping for some sign of Esme. A flicker of light too green to be the moon’s reflection was all he could see, and that happened so fast he wasn’t sure if he hadn’t imagined it. What to do?? A breeze wafted across the lake and the cold wracked him again. First things first, he thought, raising the unfamiliar wand and pointing it at himself.
He could vaguely remember a spell he’d learned when he was a student. It was an Adaptation spell. They had cast it on goldfish and then tossed the creatures into a box of sand. The fish had grown mole-like digging claws from its fins and its gills had closed. It had buried to the bottom of the box until Remus enticed it out with a fresh earthworm. That had been after it was done correctly, though. Peter’s fish had gone up like a firecracker and rained little orange scales on the whole class.
Sirius wasn’t sure he remembered the spell and he was fairly certain that it hadn’t been intended to be used on humans. Desperate times called for desperate actions, his half-frozen brain told him. Besides, he was willing to bet that he could do a spell better than Peter, even years after the fact. With that, he tapped himself on the chest with the wand and forced the words out through his chattering teeth.
He was immediately afraid that he had said it wrong when the pain tore through him. It felt like his skin had been grabbed and twisted backwards over his organs. It passed quickly and he took a deep breath to steady himself, then gagged. It was like breathing out of a chimney, scorching dry and scratchy. The cold was forgotten in a moment of panic. He also forgot to keep treading water and sank under. Two cold stripes opened on his neck and he found himself breathing water.
I have gills, he realized. He felt them flare open again and cold water seeped in. It felt weird and frightening and he didn’t want to touch them. Another brief flare of light came from the water below and he dove for it. The water parted for him easily and the cold no longer bothered him. It was too dark for him to tell what else the spell had done to him, but the results were what mattered.
Far below him, Esme was in trouble. The Magic Cancellation Curse had been slow to wear off. Perhaps sensing her helplessness, the merfolk had attacked. As Sirius approached, he could see the dim lights of their lanterns. Esme had finally been able to use magic, but she was running out of air and the blasts that she was able to summon underwater were growing weaker. Sirius could see her weighed down by her long coat as she tried to fight. Three burly mermen circled her like sharks. At every opportunity, one would attack, slashing at her with their tridents.
Threads of darkness swirled around her in the water, only visible in the light of the eerie mer-lanterns. Sirius hoped it wasn’t blood. Her rings flashed and she sent one of her attackers reeling back again. She tried to kick upwards, but another merman grabbed her coat and pulled her back down. Sirius burst into the dim circle of light and the lake people turned to see him. Then, they all recoiled in horror. One dropped its lantern.
What HAVE I done to myself if I look that bad?? Sirius wondered. In the pale green glow, he saw that he now had a slimy membrane webbing his fingers. At least my skin isn’t scaly, he thought, swimming to catch Esme. Her eyes were closed, but she struggled when he grabbed her. Bubbles escaped from her mouth and her fingers dug into his arms painfully. He wrapped his arms around her and swam as hard as he could for the surface.
The moon was behind the clouds again when he burst back into the air. He tried to take a breath and choked on it. He lifted Esme’s head above the water and gave her a shake. When he tried to call her name, only a strange wheezing came from his altered throat. Esme was gray from the cold and limp in his arms. Lorelei was floating lower than she had been. Whatever spell was keeping her aloft was wearing off. And I can’t speak to cast any new spells! Sirius fumed.
Gritting his teeth, he took a deep sucking breath of the air and forced it into his chest. He counted to five and did it again. It’s an adaptation spell, he reminded himself. I’ll just have to adapt back. It hurt even worse than before, but slowly, he felt the gills seal shut in his throat after a few more breaths. His hands were still webbed, but that didn’t bother him. He got a better hold on Esme with one hand and grabbed Lorelei’s robe hem with the other. Towing them both, he swam for the shore.
Without the moon, it was dark and clumsy going. Sirius’ legs didn’t want to support him when he finally got to water shallow enough to walk in. He hoped it was from the cold and not another bizarre shapechange. Lorelei was still floating unconscious. She was the lucky one, he decided. He set Esme down on the back and pulled Lorelei up over a pile of leaves. She was floating about three feet off the ground. He checked her pulse and it was steady. After a moment of misgiving, he peeled back one of her eyelids. Her eyes were still red, but she didn’t wake.
Esme thrashed suddenly and was still again. Sirius turned back to her. The movement had thrown her broken arm at a painful angle. He knelt beside her and gently tried to lay the bone straight again. The pain seemed to awaken her for a moment. Her eyes opened and her mouth made the shape of a scream. She seemed to recognize him and clawed at his sopping wet robes wildly, even with her bad arm.
“Easy,” he said, his voice still sounding a little hoarse. “Are you all right? What happened to the Bind?” He caught her wrists and pulled them out of his clothes. She coughed up a mouthful of brackish water and tried to force words out, but all she managed was a few stuttering sounds. She was shaking so hard he was afraid she might hurt herself worse. “It’s ok,” he told her. “I know you’re cold, but it’ll be ok. We’ll get you both inside and get some help. All right?”
She didn’t respond even to nod. Her eyes were closed again and she lay shuddering in the dead leaves. Sirius still didn’t feel the cold, but his webs were starting to recede back into his fingers. It wasn’t pleasant to look at, so he took the wand again and levitated Lorelei up to eye level. He didn’t want her waking up if she was still possessed. As a precaution, he tied her sleeves together in a makeshift straitjacket. Though as wet and pale as her sister, Lorelei didn’t seem to be affected by the cold either.
Must be the vampire in her, he thought. He wondered what to do with Esme. He could keep her warmer if he carried her close to himself, but that would also jostle her bad arm. If he levitated her with Lorelei, the trip would be smoother, but she’d still be freezing. She was unconscious now, or at least too far from awareness to voice her own preference. Her shivering hadn’t eased up, so Sirius decided to go with warmth over comfort and gathered her up in his arms. With Lorelei drifting behind him like a soggy ghost, he started back to Hogwarts.