Too close, too close.
Heart beating as if trying to escape his chest, terror swift on his heels, Merlin ran back to his little room and slammed the door.
He'd been a fool. No, worse than a fool. He'd grown careless.
He'd known for months that Arthur was watching him, sneaking little glances when Merlin was doing chores, craning his neck whenever Merlin's shirt rode up a bit, gazing at anything that hinted of skin.
At first, he thought it was harmless, that Arthur was just being an annoying prat or maybe trying to find something to mock whenever the large ear jokes or jibes about his clumsiness ran thin. He was sure it couldn't be something else, something more intimate. After all, Arthur would never indulge himself, never have a liaison with a servant; he'd been clear about such things, that forcing someone of lower rank to bend to a noble's sexual needs was dishonourable.
But even if it were possible, even if there were to be more – and Merlin could feel the longing between them growing and growing almost past the breaking point, he knew he'd never be able to give in.
Because his skin exposed every lie he'd ever told Arthur. The battle with Nimueh branded his chest; there was the leftover imprint of Morgause's chains, the sting of hideous creatures, burns and wounds mishealed from Sigan and Catrina and so many others that he'd lost count. And almost every scar had been brought about by confrontations with magic.
Arthur would be horrified if he knew the truth, would probably cut Merlin's head off and think himself lucky to have avoided a sorcerer's taint.
No, it could never be, not until magic was restored to Camelot and even then, Arthur would never forgive the betrayal.
Better for Arthur to think the scars were from other things, other mishaps. Better that Merlin bury himself in more lies than tell the truth.
The truth would only get him killed.