Alright. Here's where we start to meet up with the film canon. This anecdote is spurred by something that happened during the battle on Jotunheim in the first "Thor" film. Of course, I own nothing except for the words.

Of Frostbite

Sif had barely raised her knuckles to his door to knock when it opened and Loki grabbed her arm, pulling her inside. "You know it's not really the best time for you to call me here," she told him. "Your brother was just banished."

"I know that; I was there," he replied absently, as though, despite his words, Thor's expulsion from Asgard was the farthest thing from his mind.

Sif folded her arms. "You could show a little more sorrow – respect at least."

"Well forgive me for being a bit preoccupied," he snapped back.

"Preoccupied?" she asked, blinking at him in frustrated disbelief. "Preoccupied by what, exactly? What in all Yggdrasil could be more important to you than your brother?"

"Lots of things, Sif! Believe it or not, the universe does not revolve with Thor at its center!"

She stared at him for a moment, trying to figure out when this had become an argument. He had a hand pressed to his forehead, eyes squeezed shut as he sighed hard and fidgeted with his other hand. That caught her attention. He so rarely yelled; it was even less frequently that he ever did anything that could even be compared reasonably to fidgeting. "You are not acting like yourself," she said bluntly – a better option than punching him.

"I'm sorry; I know," he said, pressing his fingers even deeper into his temples. "I just can't seem to shake this – and I – I'm preoccupied." He was pacing around the room like an agitated animal.

"Loki," Sif said, and he stopped, looking at her. She spread her hands invitingly, any fighting between them entirely eclipsed by his strange, atypical behavior. "Talk to me."

It only took a moment for the floodgates to open. "That's why I called you here. There is something very . . . heavy on my mind, and you are the only person I could – I trust you." He stopped for a second, his mouth opening and closing around words that just wouldn't come. Finally, he forced himself to say, "Earlier, on Jotunheim – how is Fandral?"

Sif narrowed her eyes at him, growing more concerned for him every instant. "Alright," she replied.

"Still burnt?"

"Yes, though Eir will have him cured in no time."

"So," he said, resuming his pacing once more, "would you say that, logically, any of us would get burnt as well if we touched a Frost Giant?"

Everything about him was sending prickles down the back of Sif's neck – a sensation that she typically only ever felt when something was terribly amiss and she or someone close to her was in immediate danger. The feeling of too quiet and red flags and sleeping dragons. "Yes," she replied.

"I didn't."

There it was. The ax that had been hovering in the air, waiting to fall. She stared at him, unsure as to whether she should be elated or frightened. He wasn't hurt, she reasoned. That was a good thing. Still, no matter how hard she tried to convince herself of that rationale, his demeanor stopped her from believing a single word of it. "You touched a Frost Giant?" she asked, incredulousness masking the myriad of other shocked emotions coursing through her.

"He touched me," Loki explained. "Grabbed my wrist and didn't let go."

"Show me," Sif demanded, and he rolled up his sleeve, showing her his perfectly unscathed forearm. She gaped at it, wondering how it was possible that Fandral had been charred to black while he was just as fair as ever. There were not even any new scars.

"See?" He pulled his sleeve down immediately, hiding the anomaly from himself. "But it wasn't just that I didn't burn. I –" Words on his lips usually flowed like water or mercury. Now, though, they were ungainly, and he, the silver-tongued second prince, was struggling. Sif had only ever seen him so speechless once before, and that had been after his right of speech had been forcibly taken from him by some dwarves and golden thread. Even after his mouth had been freed, he had refused to speak at all for days. But he had been through significant trauma then, Sif reminded herself. A feeling at the back of her mind nagged at her, sticking her with the uncomfortable notion that there are, also, many types of trauma.

Loki took a breath. "When the Frost Giant touched me, I – my hand turned . . . cold." His voice was trembling at the memory, and he closed his eyes, forcing out two more words. "And blue."

She stared at him for too long, trying her hardest to make logical sense of what he had just told her – trying to imagine, in her head, what his hand would have looked like or how she would have reacted had she seen it. Trying to decide whether this was possible at all in the first place. Something about the prospect of it frightened her, though, and she wanted to believe that he was merely teasing her, playing a trick like he so often did. He was, after all, a flawless liar.

But the fear in his eyes betrayed him in so raw a way that she was left with absolutely no room for doubt, no matter how hard she tried to refute the possibility of it. She had known his face her entire life; she could still not consistently catch him in a lie, but she could always tell when he was being honest.

He closed his eyes, holding his trembling hand out in front of him, extended toward her stiffly as his breathing deepened and the rigidity in his shoulders tried to melt away. Slowly, reluctantly, he wrapped the fingers of his other hand around the wrist of his shaking one, muttered a cantrip, and immediately, his skin started changing.

It happened so quickly that Sif was stricken by how readily his body took on such an unnatural, frozen, horrifying hue. More startling than just the color of his flesh, though, was its transformed consistency. It was so little like flesh at all now that she couldn't help but stare at the hard, stone-like texture on the back of his hand – the ridges that carved through the skin like scratches in a flat plane of ice or scarring on a frosty boulder.

Something was wrong. Loki's eyes were pinched shut, the tight strain reappearing throughout his entire body as his blue hand shivered violently. "No – stop," he muttered through clenched teeth. She watched as he squeezed his wrist harder in his still-fair hand as if strangling the frozen hue that she could barely see bleeding up his arm and disappearing under his sleeve. His eyes flew open desperately, and he tried to pull his hand off of his own wrist; it was as though it had been soldered in place. Panic rose on his face as he twisted his blue hand this way and that, doing all that he could to break his own unrelenting grip over which he no longer had any control. "Sif –"

She stumbled backward, stifling a gasp as the blue crept up his neck, reaching its icy tendrils onto the planes of his face. Before she could even understand what was happening, he was staring back at her through terrified crimson eyes that smoldered like embers set inside a glacier. Runic markings arched over his face and all the way down his neck similarly to the ones on the backs of his hands – both of which were now blue.

She wanted to scream, or pull a weapon, or back into a corner and pray. She was staring into the eyes of a Frost Giant. And her best friend. The red eyes that inspired fear and hatred and dread, and the eyes that knew to fear and hate and dread the red eyes.

Finally, a massive, oppressive force seemed to lift from him, and he yanked his wrist out of his hand roughly. Almost instantly, the blue slunk back again, fading to his normal, pale complexion of which she had always been fond. Now, though, she couldn't stop gaping at him as though he had struck out at her – as though he was something dangerous – and she despised herself for it.

"I'm so sorry, Sif," he said, voice choked with his own fear as he reached out a hand to her. A touch of blue still lingered in the fingertips, and she tried her hardest not to recoil. "I should never have tried that. It was stupid. I'm so sorry. I did not mean to frighten you," he said, even though he sounded frightened himself. "I had no idea – I didn't know what would happen."

She stared at him, catching her breath and feeling her shocked heart rate gradually sinking back to normalcy. "Forgive me," she said, pushing off of his desk – against which she hadn't even realized she had been cowering – and very hesitantly taking his outstretched hand. "You startled me is all." Although that was only half of the truth.

He didn't try to pull her any closer to him, instead keeping his distance. "I am afraid, Sif," he whispered. "I am afraid, and you were the only person I could tell."

She had no idea what to say. To her, he had every right to be afraid. "Has this ever happened before?" she managed.

"I don't know," he said.

"How do you not know?" she blurted, only noticing how unkind she sounded once the words had flown from her mouth.

He shrugged. "I don't make a habit of shaking hands with Frost Giants. I usually let my weapons do that for me."

"So . . . this could be new."

"Or it could be old. We have no way of knowing."

Sif's mouth went dry as she considered this. If he had been born like this, it was likely a much more troubling matter than if this had simply fallen upon him recently. The likelihood of its recurrence was higher the farther back in his lifetime it went, and the likelihood of a cure of some sort was higher if it was something newer. "Perhaps Eir –" she began, but he was already shaking his head.

"I do not think that this is something medical, like an injury or a sickness," he said.

"Well then, what do you propose?"

Again, he shrugged. "Something magical."

If he was right, Sif knew he was looking at a much bigger problem. Very few people on Asgard possessed any measurable magical skill, and, in those who did, it was nominal at best. They could light a pile of tinder with a snap of their fingers, or something equally unimpressive to a true Seidrmandr. Loki was the best magician on Asgard, so, if the problem laid within the bounds of Seidr, and he couldn't cure himself . . .

"Ask your father," she said, unaware that she had even had such a thought. The words had formed almost of their own accord, tripping clumsily from her tongue, but spoken nonetheless. Then, she heard herself say, "He might know something."

Loki stared at her as though she had lost her mind. "My father. The man who fought the Jotunn army into the dust. Sif, if he ever saw this, he would just as soon slay me as look at me."

"You are his son."

He scoffed. "Perhaps it would do well to remind him of that sometime."

Pulling her hand out of his, she crossed her arms obstinately. They had had this conversation many, many times before, much in the same way that they had had Sif's nobody-takes-me-seriously-because-I-am-a-woman conversation. She was not going to get any deeper into this subject. She simply refused. As far as she was concerned, there were much bigger problems. "Even so, you said it yourself – he fought the Jotunns. He knows them better than most in the realm. There is a possibility that he could explain this to you based upon that knowledge."

He contemplated this for a moment, conflict playing across his face. She recalled his earlier statement: I am afraid, Sif. I am afraid, and you were the only person I could tell. Her heart ached at the fresh memory of his words, and she looked at him. He was so brave – he always had been. In the quiet, unknown ways, in the face of torment and tumult, behind the stares and whispers and sidelong glances; he remained resolute through praise and punishment, through golden thread, blood, and tears known to none besides she. He had always been second, in every heart, in every mind. To sit for centuries and endure – Sif admired him for it.

At last, he nodded. "Perhaps you are right," he muttered, and she didn't miss the way he unconsciously cradled his hand – the one that had been touched and transformed by the Frost Giant – carefully, as though it was truly made of ice.