Arthur's a lot more intelligent than people give him credit for. There's more beneath those blonde locks, banters, and battle strategies.
Really, there is!
Furthermore, it is because of this sheer amazing mass of brain that's stuck in the prince's skull that the royal has noticed a few things.
#1. Merlin was sentenced to execution on the grounds of sorcery two days ago.
#2. Merlin escaped the pyre using magic.
"Magic, really Merlin? Why didn't you tell me?"
Now, if it had been anyone else escaping, the prince would have expected them to have run away from Camelot, never to be seen again.
Of course this is Merlin, which brings us to the realization, or more appropriately, reminder #3: Merlin's a useless idiot.
"So, your name is Marlin?" the prince asked the new servant in the castle. The boy in question scratches his ginger head slightly, red wig almost falling off.
"Yes, your majesty," the servant replied. Forgetting to bow or lower his gaze as any other servant, or citizen for that matter, of Camelot would do in front of royalty. Then again, this is Marlin. The prince was at least a little shocked, that the youth actually remembered a title.
Oh, this was going to be fun!
"You know, Marlin," the royal said, tempted to snatch the ridiculous wig off the idiot's head, "I used to have this useless, lazy, incompetent manservant a few days back. But you look like you actually know how to polish armor. Why don't you go to the armory and shine up all the knights' armor for me?"
"Do you need to see your face in everything, prat?" the sulking manservant mumbled, stomping off towards the armory, forgetting to ask for directions even though he was supposed to be new.
"You!" the prince hear a familiar parental voice boom from around the corner, followed by the sound of his new manservant yelping in surprise. Not a second later, the young royal was treated to the sight of Marlin dashing around the corner with the king right on his tail. "Gets back here, Sorcerer!" his majesty yelled, swiping a sword in the air in a vain attempt to kill the ginger-haired convict. The king was red faced as he called for the guards.
Disappointingly, the knights never did get their armor polished. The prince blamed Marlin as the very next day the new manservant had mysteriously escaped the dungeons.
Which brings Arthur to realization #4: Merlin is a hopeless, useless idiot.
"You wish to be my manservant?" the young royal asked the man in front of him, slightly intimidated, because of his massive height, and huge muscles. A tall, muscled man conveniently named Mervin.
"Yes," said the tall, deep voiced man, forgetting, or rather never learning formalities. The prince studied the monstrous man, noting how 'manly' he was. Let's see…muscled body, tall, tanned, plenty of chest hair.
Someone was feeling inadequate!
'How did the idiot manage to get this disguise? Morphing potions?' the prince thought.
"Qualifications?" he asked, deciding to play along with the game.
"I can polish armor, mend chain mail, polish swords, sharpen swords..."
" Stop! Stop, stop, stop...Stop!" Arthur interrupted, pinching the bridge of his nose in annoyance. "You cannot do a single one of those things, Merlin, don't be ridiculous!" the prince finished, noting the childish, hurt look on Mervin's manly face.
"I can so, you prat!" said Mervin adopting a childish frown.
Of course, like all of Merlin's brilliant ideas, unlike Arthur's, which are flawless, Merlin's never lasted long. Another sorcerer eventually showed up, threatened Arthur's life, Mervin saved the day with magic, said servant being thrown in the dungeons, and then escaping. The prince decided he was going to buff up security after the entire debacle was over.
Which brings us back to Arthur's realization # 4...
"Merlin, you're a hopeless, useless idiot!"
The new servant jumped slightly, turning around in surprise sporting a 'how did you know it was me?' look. The royal grinned back from the bed, waving lazily at the other male.
"You forgot to wear a disguise this time, Merlin." Arthur pointed out.
"Oh," the manservant said, looking down, assessing that indeed he still looked like Merlin.
"Can I stay here for awhile? Morgause refuses to give me any more morphing potions."