A/N - I keep seeing stories where Arthur is either completely oblivious to Merlin's Very Obvious Magic or he knows all along and is just waiting for Merlin to tell him, so here is my take on the two ideas. I've proofread, but if you notice any glaring errors, please tell me, and let me know what you think!

-JKelly

Arthur knew.

Merlin didn't know that Arthur knew of course, but he did. After all, there were only so many mysterious disappearances and long nights in the 'tavern' that any good king could be prepared to overlook without realising that something suspicious was going on. And that's not even taking into account all the moments he'd have to say Merlin's name three times before he got a response, or the way that Arthur kept catching him staring distractedly out of the window when he was supposed to be watching to make sure his goblet stayed full (although he suspected that that one might have more to do with the boredom of the task than his manservant's secret life). Then there were the times when Merlin would say something so...profound, that Arthur knew it couldn't possibly have come from him. With all of this evidence, only an idiot wouldn't figure out what was going on. And despite what Merlin may tell anyone who'd listen, Arthur was not an idiot.

Arthur knew.

After all there was really only one reason that a man would have long, unexplained absences, be easily distractible, and have sudden bursts of wisdom that clearly came from another source.

Merlin had a sweetheart.

The more he thought on it, the more it made sense. The dresses he'd seen Merlin carrying that he insisted weren't for him? For his girlfriend! The pieces of food that mysteriously went missing from his plate? A romantic meal! The times Merlin would wake him up in the morning wearing the same clothes as the day before with rings to rival those of Saturn under his eyes? Well, Arthur wasn't sure he wanted to know quite so much about his friend's love life, thank you very much.

But that was just it - he didn't really know anything about Merlin's love life. If he and Merlin were friends (and despite all the insults and the difference in their stations, he liked to think they were), why hadn't he told him about her? Was he so untrustworthy as a friend that Merlin felt he couldn't share the more personal aspects of his life with him? Or was there something else to it?

It was with this in mind that Arthur decided to employ Operation: Prove My Trustworthiness To My Idiot Servant So That He'll Tell Me About His Girlfriend. Ok, so the name needed work, but he supposed it would do for now.

He put his plan into action one morning as Merlin was serving him breakfast.

"Merlin,"

"Yes Arthur?"

"You know you can tell me anything, right?"

Merlin looked at him suspiciously - Arthur supposed that was his own fault for instigating a conversation about feelings without being forced into it by special circumstances (such as a near death experience) or under the instruction of his wife (and honestly, he preferred the near death experiences to the chastising he got from Gwen when she didn't think he'd been 'sensitive' enough). But Arthur was a soldier at heart, so he pushed on.

"I know I don't often say it, but we are..." he nearly faltered here, but his curiosity to find out about Merlin's girlfriend won out over his discomfort with the admission, "friends, Merlin, if I'm honest best friends, and I want you to feel that you can tell me things - personal, private things - if you wanted to, that is."

Merlin seemed to be looking at him with indecision now, and Arthur could practically see the internal conflict in his mind. Time for the clincher, he thought, his final demonstration of trustworthiness.

"I am the king, after all, so I have to keep a lot of important secrets, so you know yours would be safe with me."

For a moment, something like - disappointment? Resignation? - crossed Merlin's face, and Arthur worried that he'd somehow said the wrong thing. But then, Merlin began to talk.

"Well, Arthur..." he began tentatively, and it was all Arthur could do not to lean in with excitement, "if you're sure I can talk about these things with you..."

Yes, yes! Arthur was rejoicing so loudly in his mind that he was almost surprised that Merlin couldn't hear it. Finally, he was going to get the answers he'd been after for so long! Operation: PMTTMISSTHTMAHG was a success!

"...I really think we need to talk about the state of your socks-"

Wait, what?

"I mean, you ought to think about seeing Gaius, because I'm pretty sure that no foot should be emitting that sort of odour--"

"Yes, thank you Merlin," Arthur cut him off, annoyed more by the failure of his genius plan than the familiar insults to his feet, "I think the whole kingdom must know what you think of my socks by now. That's...not really what I meant."

"It's not, sire?" Asked Merlin, looking far too innocent to actually be innocent.

"It's not. I really meant...the sorts of things you would tell a friend, you know, like details about..." how obvious could he make it here, Arthur wondered...pretty obvious, he decided, "your life and the people in it, the people you care about, things like that, you know?" His kingly demeanour was dissolving by the second here, he knew, but there was only so much room for dignity when you were trying to get information out of your best friend about their secret lover.

"Well, Arthur, as you say, we're friends, and I care about you..."

Was this it this time?

"...and it's as your friend that I say about the socks - I really am very concerned for your health - and mine if I have to keep smelling them..."

No. No, of course it wasn't. The wide eyed look on Merlin's face should have told him that he was up to something from the start.

"Merlin..."

"Yes Arthur?"

Arthur picked up his goblet and took aim.

"Getting out right away sire." Smirked Merlin, walking backwards out of the door as he ducked below the goblet's path with more grace than you'd have imagined he possessed if you saw him on a hunt.

Arthur sighed into his food, wishing he still had something to wash it down with, and mused over how his plan hadn't been such a success after all. Perhaps it was time for a new plan.

He'd call this one Operation: Follow My Idiot Servant To Find Out Who His Girlfriend Is.

Satisfied with his brand new, sure-to-succeed plan, Arthur walked over to his wardrobe to pick out the most unkingish clothes he could find. He was certain that he would have his proof before the week was out.

Arthur knew it.