“Aren’t they?” Not-Cora cocked her head. “They fell, voluntarily or no. The depths are ours. Everything within them belongs to us. The water knew this one, and she knew the water, and she breathed it willingly in.”

“She isn’t of the Moors,” said Jack.

Not-Cora returned her terrible attention to the thin, damaged girl in the black leather gloves. “So?”

“These depths are yours, but she belongs to a different sea, and that sea may have Drowned Gods of its own, and they may take umbrage at you claiming something for your own amusement that they’ve already marked as belonging to them. If the purpose of this exercise is maintaining the balance of the Moors, do you want to risk offending your alternates? I’m sure they couldn’t possibly defeat you here, in the place of your power, but…” Jack offered a delicate shrug. “The people of your protectorate are fragile when compared to you.”

“Greedy little things,” chided Not-Cora. “We never intended to keep this precious pearl; do not think you’ve won something we treasured. Still, the payment will be due.”

“No lives,” said Sumi.

“One life,” said Jack. The others turned to her. She didn’t move, but continued staring levelly at the things in Cora’s skin.

“My sister,” she said. “Jill can’t walk away from this. I would never be safe. Alexis would never be safe. I killed her once, to save people I cared about but didn’t love. To save the people I love, I’d destroy her so completely it would be as if she had never existed.”

“Without her existence, the Moon would never have seen fit to send you a door,” said Not-Cora.

Jack shrugged. “So I would have grown up innocently loveless, and never known what I was missing. I’ll pay you with my sister’s life. Is that enough?”

“Almost,” said Not-Cora. The strangeness in her voice grew stronger, like the tide rolling in. “Almost. You’ll stay, Jack of the Moors, Jack of the lightning. You’ll stay until the Moon releases you from service. Not merely on the Moors, not merely in this world, but in your windmill, chained to your lightning and your learning as Dr. Bleak was before you, and Dr. Ghast before him, and Dr. Frost before her. If your lover leaves you for another protectorate, you will not follow. You will be the cruel light to balance the killing dark, and you will know, every day, that you have no choice. You belong to us now.”

There was a moment of weighted silence before Jack laughed.