“It was,” said Oberon. “It probably will, eventually, if I’m not assassinated first. But the veil . . . it takes a lot of energy for things to move through the veil from the Otherworld to here. Exponentially more energy to move from this side, back. I am not strong enough—I can never go back.”

“Oh. Did you know that when you agreed to come?”

“Yes.”

“How could they make you do that?”

“I volunteered, of course.”

“Why?” Ángel’s heart was beating hard; he hadn’t even realized, himself, how angry he was. “To come here and die in a cage in the mountains, so that they can understand Hamilton? That’s just wrong.”

Deliberately, Oberon plucked a complicated tune, pick flashing across the strings of his guitar, muscles playing in his left forearm as he shifted his fingertips over the strings. “Don’t let it distress you so, Ángel. I was the best qualified person to come, and it’s worth it to us—to me. I am a great adventurer.”

“You are,” said Ángel, laughing a little. “You’re like Columbus, if Columbus had been by himself in a rowboat. And hadn’t done anything bad to the Native Americans.”

“Complicated metaphor.”

Oberon seemed to be soothing him with his voice, and steering the conversation to less troubling waters. But then he added, “That’s one of the points of information I’m intended to gather—how long one person can last here.”

Ángel, who’d been relaxing into the sound of Oberon’s voice, sat up sharply. “That is fucked up,” he snarled.

“No. I knew how it would be.”

“When you had sex with me, did it mess up their data?” Ángel tried to match Oberon’s light tone, but it came out bitter.

“I was never given instructions not to have sex with a human,” said Oberon, meeting Ángel’s gaze, still playing. “Perhaps it didn’t occur to anyone that I might. It would be considered rather kinky, you know.”

“Yeah. I know.”

Ángel sat back, shook the tension out of his hands, and set his fingers to his guitar again. He tried to copy Oberon’s melody. Oberon slowed down, letting Ángel follow him, and they played together for a while, a sort of dueling-banjos exercise in which Oberon played a riff and Ángel copied it; then Ángel would play, and Oberon would mirror. Adapting, improvising.

“It makes me nervous that everyone knows,” Ángel said eventually, chest aching a little.

Oberon stilled the strings on his guitar with his flattened palm. “Explain to me why?” When Ángel hesitated, Oberon said, “Once when I didn’t understand something, you told me to take your word for it. I didn’t, and I regretted it. Help me understand.”