A/N: For once, a canon representation of Arthur and Merlin's relationship, for those who miss canonicity in this world of extravagance and time of elaboration.
On his journey to the Isle of the Blessed—the first time, that is—Merlin had plenty of time to reflect on why, exactly, he was doing this. Namely, riding off to his death. Obviously, the reason was simple and in fact explicable with just one word. Namely, Arthur.
It was what that one word meant that was slightly more difficult to understand.
But, as previously mentioned, Merlin had quite a bit of time on his hands. Not enough. But it'd do.
First and foremost, it was his destiny to protect Arthur. His duty, his responsibility. It was quite simple: he had to keep Arthur alive. For the sake of the kingdom, for Camelot and for Albion which had yet to be united, Arthur had to live. For the sake of magic, which had to be legalised and freed. For the Lady Morgana, who he thought needed to be told the truth, for the Druids, who had to hide. And selfishly, for himself. There was a growing part of him that was hugely impatient for a time when he could use his magic openly.
Even more selfishly, it would be nice to get some credit for saving Arthur—and the kingdom—repeatedly.
Not that it would ever happen, Merlin hastily reminded himself. He was about to die.
It was surprisingly easy to forget that.
And that was the reason that this whole sacrificial journey was so complicated. He wasn't thinking about dying, or about sacrifice, or whatever. He was just thinking of why Arthur had to live. He knew that if the Dragon had never told him how much good Arthur would do, he wouldn't have put anymore thought into riding off to die, either.
Why? For the love of magic, why?
Arthur was a prat. A royal prat, in fact. He wished he'd said that to him before this, just to see the look on his face. As a master, he wasn't the worst, not by a long stretch, but he wasn't the best either. Take Morgana, for example. She let Gwen have the odd afternoon off, didn't use her as target practice and absolutely never called her an idiot. On the other hand, at least Arthur didn't need comforting in the middle of the night after suffering horrendous prophetic nightmares. And he did listen to Merlin every now and again.
Well. Occasionally. Sort of.
Anyway, the point was that Arthur was just another noble master, albeit a rather more important one. Theoretically, he was.
Except he wasn't.
Because there were those little things he would do which, now he'd thought about it, really weren't so little. Such as ensuring that Gwen kept her job and her home after her father was executed for conspiring with sorcerers. Or riding off on a fool's errand in order to save Merlin's own life, nearly getting killed in the process. Twice. Or helping to save that Druid boy (though best not think about that). Or leaving his very kingdom to risk his life (again) for the sake of a village in which Merlin didn't even live any more.
It was at moments like those when Merlin really remembered that he was serving a prince.
He sometimes wondered if there were times when Arthur really didn't want to be a prince. Obviously not most of the time. Most of the time he loved the adoration and the praise, and he enjoyed having the power to change things, but sometimes... There were downsides to being a prince that Merlin had never even considered before meeting Arthur. Like the complete lack of thanks for risking his life again and again. He could empathise with that one; it was a bit like being a servant, really. Serving the people, because it was your job. He had no choice but to go out and fight for Camelot, and yet still having no power to change things. The important things, at least. And anything concerning magic.
Sometimes Merlin wondered if Arthur would really go as far as the dragon said he would. Sure, he had let the Druid boy go free, and he hadn't been too upset by Will's supposed sorcery, but by no stretch of the imagination did that mean that Merlin would be willing to go up to him and say something along the lines of, "Oh, hi Arthur. By the way, I'm a warlock but don't get annoyed about that—I've been using my magic generally to save your life. And did I mention that I'm destined to be part of your fate?"
Actually, Arthur would probably laugh. Or roll his eyes and ask who he was trying to save now. One of the two.
That was a pain, too. Because Arthur thought that Merlin was just an idiot with no natural abilities whatsoever. He definitely appreciated the only attempt to save his life that he actually knew about, as well as how much Merlin actually cared if he lived or died, not that he would ever tell his long-suffering servant that, but for all that, he still thought Merlin was primarily useless. That hurt, every now and then. Normally it was quite amusing, but occasionally, it would have been nice to be appreciated for what he was.
There. He was thinking in the right tense now. Suddenly death wasn't seeming so appealing.
He wanted to see Albion as Arthur would make it. He wanted to one day confess the truth of his power. He wanted most of all to see Arthur become the King that only he could. He wanted to feel pride squeezing his heart as Arthur was crowned.
Merlin had never known a brother. He had considered Will to fulfil that role back in Ealdor, but now he saw that he had been wrong. It took more than being a playmate, a confidante, trusted. Arguably, Arthur was none of those things. Definitely not the first two, anyway. But it felt to Merlin as though Arthur were a part of him, and maybe that was just because of their entwined destinies, but maybe it wasn't. Maybe it had more to do with them, not as master and servant, nor as prince and warlock, but as Arthur and Merlin.
The latter winced as he thought this, imagining Arthur's bemused and disgusted expression should he ever hear these thoughts, but it didn't stop him thinking them.
That, surely, was brotherhood.
Because Merlin loved Arthur, with more than the devotion that a subject should afford his prince, and were he not about to die he would never ever even dream of there being the slightest possibility of his one day maybe thinking this. And it was obviously very, very, very platonic, if there were degrees of platonicity, if indeed that was a word. But still. He definitely loved Arthur, and couldn't help but think that Arthur might love him too.
He did not just think that. He really did not just think that. No, really. Oh, what did it matter? He was going to die anyway.
End of story.