AN: I didn't post this here earlier because I was under the impression the site banns second person fic, but re-reading the guidelines I realised that they do make it pretty clear the ban only applies to interactive stories (in which the "you" means the reader).

Set after 1x13 (spoilers, obviously).

Disclaimer: I don't own BBC's Merlin, etc etc.

edge of the coin

If anything, it should have happened the other way round. It would have, before your fight against the Questing Beast; you don't know why, but this has changed it.

They reach you easily; once, you would never have let this happen, but you've learned to value the lessons above the person who gave them. And the law, this law, is cruel and pitiless in Camelot, even for you, but you're the crown prince and Uther won't live forever, and, if you dare look for them, you will always find allies even against the Crown. It's a harsh lesson.

There are two of them, standing before you with a strange mixture of deference and defiance. They won't plead and they can't demand, or maybe it's the other way round, but you're not going to spare them this; you listen, the account of attacks against old, unlawful vestiges of the old religion that Uther hasn't found (you think, treacherously: hasn't dared to find), but all you can say is:

"I will not act against the king."

You have to fight down the urge to take revenge for the feeling of helplessness they have raised in you and add: "and neither should you." You don't say that the minute they have left, you will be in the throne room demanding to know how this can have been kept from you.

The druid, the older one who has been silent for most of the meeting, looks you square in the eyes and says:

"It is not the king's doing. It is your warlock."

You should be shocked, but instead everything falls into place smoothly in your mind, at last. You're ashamed of how tempted you are to say that you don't know what they mean; to rebel against such an accusation; to continue to pretend to yourself that you can't see. The pretending, the wilful blindness are not only comfortable, but necessary for the precarious balance between you, you don't know what will happen if you let it break. But this is about Camelot and your people, no longer only between you and Merlin.

Merlin. You almost want to laugh at the expression the druid used, like Merlin is in any way yours.

You look right back at him.

"I will make it stop. You have my word."

You can't take it back now, not without giving up everything you are.

You know, of course, that of late, Merlin has been absent very often. But you are used to that by now: Merlin never quite grasped the notion that he's supposed to always be in reach, even when he's not immediately needed, like a temporarily discarded object. You yelled at him, of course, but you never worried.

But you noticed, and you remember.

You pick one instance at random, late in the same evening – you promised it would stop and you can't stall – when you're almost sure you won't be disturbed. Merlin stands in front of you in front of the fireplace, wide-eyed and shaken, the very image of guilt, and mouth drawn to a stubborn line, ready to deny as soon as he finds his voice.

"You will stop," you say before he can voice his protestations (he's planned nothing, of course, no lie, no excuse, for this eventuality), not a request, not an order, a statement.

"I don't know what you're talking about," Merlin finally manages, hands clenched to fists by his side, gaze unchanged, and there's something pleading in his voice that makes you want to back down, and you can't.

Less than an evening of absence, and a whole temple vanished into nothingness, one warning, one chance for surrender and a free pass for the children – more than Uther would have given, and only because of this did the druids even know – and then stone boiled to lava, and nothing left behind. You tell him this. Merlin pales, and there's a painful moment of tension, before he crumbles.

"I can't. I won't. I know them, and you have no idea what they'd do to get a hold over you."

"It doesn't matter."

And it doesn't. It doesn't make a difference that these are people you would arrest and maybe take to a worse death if you could. You won't support your father's unfair laws on magic and let "your" warlock fight for you in secret.

"It does to me," Merlin snarls; he glares at you, and adds: "You can't make me stop."

It's strange: you're not afraid, but you feel you should be. Merlin is maybe the worse liar you know, and yet he's successfully worn this mask this whole time, and you have no idea what truly lies behind; he's lied to you, tricked you, and if he's this powerful, even the fear of exposure and death is not an excuse.

Merlin doesn't move when you step forward, doesn't resist when you grab his wrists, even though your grip must be painful, doesn't look away when you stare at him intently.

"I won't let them," he says, and when you don't let go, he repeats fiercely: "You can't stop me."

His eyes turn golden, and the skin under your hands flares with heat so suddenly that you almost let go in surprise; then you hold on tighter: only a little more, and you would grind his bones under your hands. With little more than a thought, he could, without any harm to himself, make the heat under your hands so unbearable than you would burn.

But he won't. But you won't.

It's Merlin who yields first. Not, you know better, in defeat, in acceptance: only because unlike you he has not, for as long as he can remember, trained to control his strength, not with the same discipline.

You release him only when the heat has died down completely. Your palms still hurt, you won't be able to wield a sword without pain. You will both have bruises, from this.

"I can't let you do this," you say (like you can stop him). "These are my people as well, and it's my duty to protect them."

Merlin doesn't look at you.

"It's mine to protect you."

"Not like this." You wait for him to look back up, to add, a hint of annoyance slipping into your voice you've tried to keep even: "If falling on my sword is what it takes, I will do it."

It's overly dramatic and cruel – you're not sure you would not hate Merlin if he made a threat like that to you – but it works; the stubborn decision in Merlin's face vanishes, replaced by fear.

"I could..." he begins, and trails off.

You wonder about the true extend of his power, if he could make you unable even to take your own life, if he could manipulate your very mind; you're almost certain he could, that there are no limits to what he can do.

And it's infuriating, in the way everything about Merlin has been infuriating since the very first day, this power that is so far beyond your authority and anything you can hope to fight and master; a yet, because this is Merlin, the temptation to give in to it is just as strong as the desire to control: so powerful no-one could expect you to challenge it and be successful, and the possibility of abandonment of all responsibility that Merlin's "I could" implies is sweet and beckoning like nothing you've known before...

Something must show on your face, you don't know what, maybe only the naked want, but whatever it is, it makes Merlin back down.

"I didn't mean..." he stammers, and you're quite sure that he did mean but regrets it. "I wouldn't..." He glares at you. "Why don't you let me explain why instead of telling me to stop? You don't always know best. Actually, most of the time –"

You glare back, and the familiar feeling of annoyance is good, almost cleansing.

"So why didn't you explain before acting behind my back then?" you counter.

There's a long silence as you glare at each other. At least there won't be any bruises this time.

It's a lot to digest, Morgana's visions, the dragon, Merlin's single-minded angry protectiveness, the hidden followers of the old religion who wait for your father's death and will not wait for yours if you are not the king they want.

It's almost morning by the time you get the promise you wanted; Merlin is sitting on the floor, leaning against the bed where you've laid down, legs drawn to his body, and you can read his anger by the stubborn curve of his neck. You twist his scarf between your fingers and can't quite remember when you removed it, though you remember the gesture and the feel of the knot giving way under your fingers, the fabric sliding over your palms, and the small shiver under your fingers as they touched his skin.

"You get used to it," you tell him.

He cranes his neck to turn and look at you.

"What?"

You grin at him. The lack of sleep and the knowledge that the sullen manservant who'd sitting by your bed can unravel the world with a spell make you feel a little light-headed.

"To being challenged," you say. By arrogant idiots who don't know their place, you're tempted to add, but Merlin would leap on the opportunity to point out you're insulting yourself.

Merlin gives you that look he sometimes gets, like every one of your unkindnesses is a completely unexpected shock to him.

"I hate you," he informs you after a silence, but he's smiling by then, so you just send him off to get breakfast.

(You see him glancing at the scarf in your hand, so by the time he's reached the door and his eyes flare golden, you're prepared enough to hold on.)