“My dear boy,” said Belial. Cordelia unsheathed Cortana; she saw Belial flinch almost imperceptibly, though he still refused to look at her. “My dear boy, there is no need to trouble yourself that your dear Grace lied to you.” He gazed lovingly down at Jesse’s left hand, where a Voyance rune gleamed, new and black. “There was a time, you know, when I feared your mother would never procreate. That there would never be a James Herondale. I was forced to make alternate plans. I placed an anchor in this world, sunk deep into the soul of a baby boy when his protection spells were placed on him. Little Jesse Blackthorn, whose mother didn’t trust Shadowhunters but did trust warlocks. Emmanuel Gast was easy enough to threaten into obedience. He placed the protections on Jesse, as instructed, and a little something extra as well. A bit of my essence, tucked under the skin of the child’s soul.”

Cordelia felt sick. A Shadowhunter’s protection spells were precious, almost holy. What Belial had done felt like a nauseating violation. “But James was born,” she said. “So you didn’t need Jesse after that, did you? Is that why he died?”

“I didn’t kill him, if that’s what you’re asking,” Belial said. “His own mother did. She let the Silent Brothers place a rune on him. I warned her not to let them interfere. The angelic runes of the Gray Book reacted quite badly with the demonic essence deep inside him. So…”

“He died,” James said.

“Oh, yes, quite painfully,” said Belial. “And that would have been that, really, but Tatiana is a stubborn woman. She called on me. I did owe her a favor, and I have my own sense of honor—”

James made a scornful noise. Belial widened Jesse’s green eyes in mock horror.

“You forget,” said Belial. “I was an angel once. Non serviam and all that. Better to reign in Hell. But we keep our promises.” He stretched luxuriously, like a cat, though his grip on the sword—its hilt, Cordelia saw now, carved with a design of thorns—never faltered. “I ordered Gast to preserve Jesse’s body. To keep him in a twilight state, not quite dead and not quite alive. During the day, he slept in his coffin. At night, he was a ghost.”

Cordelia thought of Lucie. Lucie, who could see ghosts. Who had been so secretive lately. “All the necromancy Tatiana was doing,” she said slowly. “The dark magic that got her exiled to the Citadel. It wasn’t to raise Jesse—it was to keep him preserved like this?”