Magnus scrawled a couple of lines on a piece of paper and handed it to Alec. "In the end, when we exchange rings, we'll both say this. Okay?" Alec read the paper and shook his head, pushing the paperback toward Magnus.
"No, Magnus, I won't let you say that. No way."
Magnus caught Alec's wrist. "Listen to me, Alec. This is forever. Our marriage, my love for you, all of it, it's forever. The fact that you are mortal doesn't change anything. I didn't write a single thing on there that isn't true."
"But, Magnus, promising to love me for the rest of your life? It's too much."
Magnus dismissed this. He knew how he felt about Alec, he knew he would love him as long as he lived, maybe longer. He met Alec's eyes, hesitantly, knowing what Alec would say about his next comment.
"Alec, there is a spell I want to perform at our wedding. It's a traditional warlock wedding spell." He paused as Alec's eyes narrowed suspiciously. When Alec didn't comment, he went on. "The spell will bind our souls together…forever."
"Not," Alec stated firmly, shaking his head.
"Alec, just hear me out. Please." Magnus said as Alec continued to protest.
"No, Magnus. What the hell are you trying to do? Torture yourself? I'm mortal, I'm going to die one day. Don't you get that?"
Magnus dropped his eyes to his lap and said in a small voice, "Of course I get that. Can I explain the spell before you completely reject it?"
Alec folded his arms in front of his chest, defiantly, but halted his objections, momentarily.
Magnus pressed on. "The spell will bind our souls, yes, but it's meant to be between living immortals. It will have its effect while you are living. It will mean that we will always be drawn to each other, will always want each other. Even if we are separated, our souls will seek the other. It's a spell version of soul-mates, but binding. It's not unlike the parabatai ritual, but in this case, it's supposed to be between people who are in love with each other. Do you understand?"
Alec nodded and thought it didn't sound too terrible. After all, he had been willing to give part of himself to Jace, why not Magnus, the man he loved more than anything else.
"What happens to you when I die?" He had to know. He had a vague idea of what would happen to Jace through the parabatai rune, and he was reluctant to do that to someone else he cared about.
Magnus seemed unenthusiastic about replying. He studied his hands, which were folded in his lap. Finally, he said, "The thing is, Alec, no one knows. The spell is so rarely performed because warlocks so rarely marry. And warlocks are immortal. But my best guess is that the spell will break when you die…unless…" he trailed off.
"Unless what?"
"Well, what happens to your soul when you die? Will it go to Heaven? Is there an afterlife? Do you believe, as Jem Carstairs does, in reincarnation?"
"Oh," Alec said. He didn't know what he believed as far as an afterlife was concerned. He was the most religious of his family, believing in God and Angels, even before he saw one. But how could anyone know, for certain, what would happen after he died? "I don't know, Magnus. This seems risky for you."
Magnus flashed a small smile at him. "Alec, my heart and body and soul will love you and want you forever, whether we perform this spell or not. The spell is my proof to you, proof that you are The One for me, the only one for me."
After some time, and still, with some uncertainty, Alec said, "Alright. I agree to be part of this spell."
Magnus took both of Alec's hands in his and said, "Thank you." And then kissed him.