So I was working on a different fic entirely, but then someone on tumblr said something and I wrote this instead, so you can blame prince-pratdragon for this one.

Disclaimer: I don't own anything. I don't have anything clever to add, I just don't own it.

Green-Eyed Monster

*.*.*.*.*

She's just a visiting princess. There's a treaty that's been in the works for months now and, before everything is finalized, the king whom Arthur is making the treaty with, whose name Merlin never cared to learn, thought it would be a good idea to send his daughter, and a few members of his court, to Camelot to meet King Arthur Pendragon and his own court. She was just meant to visit for a few days, but Camelot is so amazing and there is so much to do and see that she extended her trip by another week at least.

She's a good person, Merlin supposes, polite and royal, pretty enough with her long brown hair and her green eyes that remind Merlin of a dirty pond. He's been spending enough time in her presence that he feels like he should know more about her, but she's fairly soft-spoken around the servants, and only seems to come to life when she's around Arthur, even though she mostly just listens to what he has to say and says very little herself—and the two have been spending quite a bit of time together, Merlin has noticed.

It's not like he wasn't expecting that, because she's visiting royalty and he's the king so, obviously, he's meant to spend a bit of time with her showing her around and whathaveyou. However, Merlin has seen his king around visiting royalty before, and he has never acted like this—never been so… himself. He smiles at her as though he's known her for ages, he speaks almost as freely around her as he does when he's just around Merlin, and, to be honest, he touches her—almost seems to be flirting with her—far too much for Merlin's liking.

It's innocent enough, of course—he escorts her around the castle, she hangs off his arm in that royal and proper sort of way, and he guides her towards the table, or out of the way of a servant or that one horse that got away from Merlin near the stables that one day, by her dainty elbow—but it still bugs Merlin enough that he has to roll his eyes every time he sees the pair of them.

And oh God, the way she laughs at Arthur's completely stupid jokes—her face pinched up, hand coming up to stifle her laughter that's almost like the tinkling of some very annoying bells—it's enough that Merlin soon begins to dread the time he will spend in their company. Indeed, he starts looking for any excuse he can to get away from them: Gwaine wants Merlin to ride out with him to attend to some very important knight business, or Gaius wants to teach him how to make a very important, life-saving draft so he needs the next couple of hours off—if Arthur doesn't mind terribly.

And he never does, so Merlin slips away, still rolling his eyes at the way the princess—Princess Adeline—laughs at Arthur's jokes, and smiles warmly at him when he's not looking, and the way her eyes crinkle up when he speaks to her—it's ridiculous and, from what Merlin knows, completely and utterly un-princess-like, not that Merlin actually knows much about how most princesses act, but…

He doesn't even consider he might be jealous of her until Gwaine mutters something about a green-eyed monster under his breath when he observes Merlin glaring across the table at Arthur and Adeline at a feast one night.

When Merlin questions him about it, he shrugs, "I know what jealousy looks like, Merlin, and you are jealous of our dear Princess Adeline, aren't you?".

Merlin scoffs at him, "Hardly anything to be jealous of…!"

Gwaine doesn't say anything in response, and for that Merlin is grateful, because, wow—is he jealous of Adeline? No. No way. Why would he be jealous of Adeline? Just because Arthur is spending all his free time with her and he's doing everything he can to make her smile and he touches her elbow like she's made of something precious and breakable and he looks at her like he'll be completely lost when she leaves again and, okay, he does look like he might be falling a bit in love with her, but that's none of Merlin's business and she is a princess and Arthur is a king and so it just makes sense, right?

But he spends the rest of the night with a knot in his stomach and a sort of venom that rests on the tip of his tongue whenever his eyes catch on Arthur and Adeline, and if that's from jealousy then fine, so be it, he doesn't care anymore.

He spends a few more days twisting the thought and feeling over in his mind and in his gut.

Jealousy.

He's felt it before, of course—who hasn't?—but it's different this time. It's a tumbling, twisting, knotting, dreadful sort of feeling that makes him hate Adeline, and he knows he shouldn't because she seems a decent enough person, but… He admits to himself, in those nights after Gwaine helps him put a name to the feeling, that… it should be him—he wants it to be him that Arthur fusses over, that he looks at like that, that he sits next to at feasts and smiles at like that, and maybe he's wanted that for a long, long time now…

He can't do anything about the feeling, of course, because at the end of the day Adeline is a princess and Merlin is a servant, and if he thinks for one second that Arthur would ever pick him over her, or someone like her, then perhaps he's gone just a bit mad…

However, the night before Adeline is to leave to return to her own kingdom, Merlin is unfortunate enough to be there as Arthur escorts her back to her chambers and wishes her a good night. Just before she goes into her chambers, she leans up and pecks Arthur on the cheek—really, it's the sort of kiss Merlin's mother greets him with whenever he goes home for a visit, or the sort Gwen leaves him with whenever they have a chat about something that's been bothering Merlin or weighing heavily on him—but… something about the way Arthur leans into it, something about the way Adeline says, "Pleasant dreams, my lord," just before she shuts her door, makes something within Merlin… snap.

With his fists clenched, he turns about and tries to fall into line behind Arthur on the way back to his chambers. If Merlin can simply make it through the rest of the night without saying or doing anything completely stupid, all should be well…

"Shame Princess Adeline leaves in the morning, isn't it?" Arthur asks, casting a glance back at Merlin.

And it's so innocent a question—there's nothing any different about the way he asks it than it would be if it was a king or prince who was visiting instead—that Merlin surprises himself when he takes a few quick strides to catch up with Arthur, something bubbling in his veins that he vaguely recognizes as jealousy tenfold as he grabs Arthur's wrist to spin him around to look at him.

Arthur brings his eyebrows together in confusion, "What are you doing?" hangs off the edge of his tongue and the curve of his lips. But Merlin silences him even further when he backs him against the stone wall of the hallway. Arthur's eyes widen slightly and he's watching Merlin, frozen and silent in a way that Merlin is completely unaccustomed to.

Merlin isn't quite sure what he's going to do—not really, even though his heart has been thudding in his ears for some minutes now and there's something jittery and light pulsing against the jealousy in his veins and in the pit of his stomach—until his lips are on Arthur's a second later and his hands are knotting themselves in his hair, tugging and playing as he presses himself against Arthur, angry and sorry and wanting and yet so fucking satisfied as he allows himself to feel lost and hopeless and yeah okay, maybe a little more than in love with this idiot who's probably going to marry that princess with eyes that remind Merlin of a dirty pond, and he's probably going to be sacked as soon as his lips are off of Arthur's, but at least he will have this—this moment of passion and his lips finding Arthur's again and again and fucking again…

He doesn't even notice that Arthur's arms have wrapped themselves around him—one around his waist, the other on the back of his neck, keeping him close—until he notices—and is Arthur kissing him back?

"—what—?" Merlin pants, finally pulling apart for a breather, his eyes hooded as he considers Arthur's flushed cheeks, his plump lips, his heavy breathing, the way he almost seems to be begging for more as he looks over Merlin in the same fashion.

"… I think… Merlin, I should be asking you that…" Arthur tsks, his tone as light as it could possibly be considering how husky and spent he sounds right now.

Merlin just smirks in response, something else entirely fluttering in his stomach, because he is the one who did this to Arthur, not Adeline, and if this whole situation makes him a terrible person…

He leans forward and catches Arthur's lips again, and there is still something so… raw about the way Merlin kisses him this time, but also something quite pleasant that settles over him when the kiss slows and one of Arthur's hands finds its way to cup Merlin's cheek. The kiss melts from something angry and desperate and borne of a jealous rage to something right and warm and like nothing else Merlin has ever felt before in his life.

Somehow, Arthur manages to detach himself from Merlin, and get out from where he has him pinned to the wall, and it's more the fact that Arthur can stop kissing him long enough to do so than the actual act of him doing it—because Merlin's legs are more than a little wobbly by now and Arthur was the only thing keeping him from sliding to the floor—that surprises Merlin. He's almost upset for a moment, because for a minute he had genuinely thought that Arthur was enjoying this just as much as Merlin was—

Except Arthur is grasping Merlin by the sleeve and tugging him down the hall, his pace desperate and quick. Merlin's heart is beating too fast, his blood rushing through him in a way that is making it hard for him to think, so he doesn't realize where Arthur might be leading him until they're in Arthur's chambers and Arthur is locking his door. Something flashes in his eyes then, and he pins Merlin against the door, his breath hot and ragged just before he kisses Merlin, his lips rough and wonderful as he leans into Merlin, moaning and groaning into the kisses in a way that lights a fire within Merlin.

And that's almost enough.

As they kiss again and again and again and their clothes almost seem to shed themselves in a trail that leads to Arthur's bed, as Merlin pins Arthur to the bed and is moaning his name in pure want—it's… almost enough that Arthur wants him like this, but… just not quite.

Merlin pulls back, leaving Arthur to look up at him in confusion and almost concern. He bites his bottom lip, deciding that this has gone far enough—no matter his feelings for Adeline, he just… he can't be with Arthur like this if he—

"What is it?" Arthur asks, his voice ragged and worried in a way that sends a pleasant sort of thrill down Merlin's spine.

"You and Adeline—" Merlin sighs, swallowing. "Aren't the pair of you—you know?" He asks, sorrow and regret making themselves known against the pleasure he should be feeling right now.

"No." Arthur says, shaking his head, still looking up at Merlin who, despite his words and intentions, is still straddling Arthur's naked form. "No. You know she's just here because… because of the treaty."

"The way the two of you have been, I mean," Merlin shakes his head. "She looks at you like… like you're her sun or something. And you… you've not exactly been turning down her advances!" He exclaims, more venom in his tone than he had intended.

"Oh for God sake!" Arthur groans, rolling his eyes as though he isn't currently being pinned down by his manservant. "Is that what this is all about? You're jealous of Princess Adeline?" He demands, scoffing at the very notion, which, yeah, okay, maybe it is a bit ridiculous when it's said aloud like that…

"No!" Merlin insists, but—too late.

"You idiot…" Arthur chuckles, sitting up just enough to grab Merlin by the nape of his neck. He pulls him down and kisses him sweetly, smiling against his lips before he pulls back just enough to speak. "Adeline's older brother died on the battlefield some years ago," he explains gently. "And I… remind her of him. That's why we've been spending so much time together, you… clotpole."

"But…" Merlin sputters, realization settling in as something loosens within his chest. "So… you're not in love with her?" He asks, when all other words fail him.

"If I was in love with Adeline," Arthur sighs. "Do you really think I'd be here, doing this with you?"

Merlin 'hmms' to himself, nodding slightly. He can't help the relief he feels right now, the way he smiles at Arthur's words, giggles like a fool when Arthur rolls his eyes again and demands that Merlin kiss him again—if he's done being completely stupid about everything.

Merlin indulges him, leans down and kisses him, losing himself in passion and freedom and relief and love as they spend the night rolling around the sheets, Merlin's name the only coherent thing that tumbles from Arthur's lips for the rest of the night—and vice versa, of course.

When morning comes and they see Princess Adeline—whose eyes seem to remind Merlin more of the forest in spring time than a dirty pond, when he really thinks about it for a minute—and her court off… Merlin truly wishes her nothing but the best, all his animosity towards her lost on Arthur's bedroom floor in the best possible way—he can hardly find it in himself to feel anything negative towards the girl when she sees Arthur as nothing but a reminder of her dear deceased brother.

And anyway, Arthur made a point, just that morning as they were laying in bed together, to tell Merlin that there will definitely be repeat performances of the previous night in the near future, so Merlin can't help but be in a great mood for the rest of the day.

*.*.*.*.*