Merlin hissed loudly as Gaius poured the steaming potion over his head. Arthur held his breath, waiting while the potion sparked, smoking and reeking of burnt fur. And then Merlin was okay, standing there, all himself again - yes, his manservant was back, and safe, and-

No.

Oh, no no no.

"Gaius," Arthur asked weakly. "I don't think it…"

"It was a very powerful magic, sire. I've done as much as I can."

"But my father-"

"Will just have to deal with it," Gaius said blandly. "You do feel alright, don't you, Merlin?"

The young man smiled and stretched his limbs. "Perfectly fine, Gaius. Thank you."

"But what about me?" Arthur protested.

"You will have to deal with it too," Gaius told him.

And who was he to argue with The Eyebrow?

It had its advantages, Arthur supposed. Merlin could flatten his soft black ears until they lay flat against the top of his head, and hiss and growl and grouse at Arthur about how unhappy and underappreciated he was, but nothing could conceal the deep, involuntary rumble in his manservant's chest - a low, contented thrum that soon formed the backdrop to Arthur's days.

"We can't have him around the palace!" Uther screeched upon seeing the young man. "What will the neighboring kingdoms think?"

"It isn't his fault!" Arthur protested. "We did all we could."

"You manservant has...has…." the king was lost for words, and his face slowly turned a fascinating shade of purple. "They're twitching!"

Merlin peered at them over the shallow dish of warm cream he held cupped in his hands, then went back to sipping at it as if he were the only person in the room. The soft vibration started up in his chest again, and Uther pointed at him, a vein throbbing on his forehead.

"And he does that!"

"That is the least of my worries," Arthur replied.

"Is it?"

"It's soothing, and helps me think."

Merlin smirked into his cream.

"Gaius said he fixed him."

"He's not broken." He was strange, granted, even more so than before, but Arthur wasn't complaining. And he certainly wasn't sacking Merlin.

"I insist you sack him."

Arthur sighed. He needed to have this conversation somewhere where Uther wasn't constantly looking at Merlin's new quirk. "Merlin?"

Merlin caught Arthur's eyes across the room and blinked once, slowly, then returned to his cream, licking the dish clean before lifting gracefully to his feet and prowling soundlessly to the prince's side to rub his head against Arthur's temple, rumbling loudly. The king glared at them, and Merlin hissed softly at Uther from behind Arthur's shoulder, ears flattening into his unruly hair. Arthur reached back to quiet him before the king got even more angry, and Merlin bit his fingers, gently, half playful, half defiant. He must be tired, to not be keeping his behavior passably human as he usually did in Uther's presence.

"Merlin," Arthur muttered warningly.

The rumbling and soft growling stopped abruptly and Merlin let go of his fingers. "Sorry."

"The steward told me the rats are trying to get into the grainery again."

Merlin's eyes flashed. "They wouldn't dare."

"Apparently they do. I'd like for you to take care of them."

"Now?" Merlin's gaze slid longingly to the rug and the cozily crackling fire.

Arthur reached for Merlin's head and slipped his fingers into his hair just behind his ears. They pricked all the way to the black tufts at the end as he rubbed gently. His servant gave him a resentful glare even as he stood on tiptoe to press against Arthur's palm - Merlin hated this gesture as much as he loved it. Uther folded his arms.

"If you wait until tomorrow," Arthur admonished, "they will be in the grain supply." He leaned closer. "Because they have no fear of you."

Merlin pulled away, hissing low in his throat. "They will. I will slaughter them and bring you their mangled corpses." He spun and dashed for the door, slamming it shut behind him.

"You can't be serious," Uther sighed.

"I am perfectly serious."

"The boy's condition is unnatural!"

"If Merlin hadn't jumped in front of that spell, I would be the one with ears and an obsession with eradicating the population of vermin. I won't show my gratitude by putting him out of a job."

"He only did his duty as your servant."

Arthur threw his hands in the air. "How many servants are that loyal? Really, Father, you have to admit he goes beyond duty - your manservant was under the table, as I remember, not throwing himself between you and a flying spell."

"You are incorrigible."

"Like my father, then."

"Very well. But one toe - one fingernail - out of line," Uther stuck his finger under Arthur's nose, "and the boy and his condition go in the moat with a bag of rocks."

The king whirled and stalked from the room, leaving the door swinging on its hinges until one of the guards outside awkwardly stepped in to close it. Arthur went back to his paperwork. Merlin would probably put far more than a fingernail out of line, but it wasn't like he could do anything about it.

Arthur changed for bed by himself - apparently Merlin was still hunting rats in the royal cellars - and doused the candles before crawling in between the chilly sheets. They warmed quickly enough, and he was comfortable and drifting off to sleep when the mattress dipped beside him and something smacked his face.

"Arthur."

The prince groaned and buried his head into his pillow.

Hands pawed his face mercilessly. "Arthur."

"What, Merlin?"

"I slew them all."

"Good job. Go to bed."

"I'm hungry."

"Eat a rat then."

"Just because I like hunting them doesn't mean I don't think they taste nasty."

"Go to the kitchens."

"Cook threw me out," Merlin sulked, pushing his hands against Arthur's side. "She says I steal the cream."

"Do you?"

"Of course not! You think I'm some kind of vulgar rapscallion?"

"Yes."

"I will bite you."

"You woke me up."

"I'm hungry!"

Arthur sat up, nearly smacking Merlin in the nose. "Doesn't Gaius feed you?"

"I spend the whole evening fighting rats for you, skip a nice fire, and supper, and you send me off to eat porridge?" Merlin's ears drooped pathetically.

"Fighting rats?" Arthur asked incredulously.

Merlin tilted his head. "Have you ever killed two hundred twenty-seven rats with your bare hands in one night, sire?"

"Two hundred?!"

"And twenty-seven," Merlin added smugly. "And the royal stores are secure, from nibbling rodents, and from infectious diseases."

Arthur groaned and rubbed his face. "There's cold venison on the sideboard. Go eat that and let me sleep."

Merlin trilled and rubbed their heads before leaping off the bed and clattering into the sideboard. Arthur settled back down in his blankets, listening to the rumble and contented growls of Merlin's midnight supper. He was falling asleep to the thrum of Merlin's low purr when the mattress dipped again.

"What now?" he grumbled.

"Good night."

"You're not sleeping here."

Merlin turned on his hands and knees, making a nest of the ruffled blankets and extra pillows on the other side of the bed. "It's soft."

"You're my servant, Merlin, in case you've forgotten."

"I'm not your servant." Merlin stretched luxuriously from the tips of his fingers down to his toes and curled up in his appropriated blanket-nest next to Arthur, smiling at him, slitted pupils wide and glowing a little in the dim light. "You're my prince."