Merlin is a cat!!!

It was a well known fact that Uther despised cats.
Merlin had seen many feline drowned in rivers or burnt at the stake in the palace kitchens to be served to the King in order to slake his deranged tyranny.
Which is why it was a good thing that Arthur didn't notice that Merlin was a cat and happily employed him as a servant.
Merlin had done the prince a great many services over the years, like saving his life!
He had jumped on the prince's chest causing them both to go falling to the floor and out of range of an evil witch who commanded evil, twitchy,  delicious looking birds into the air around Arthur.
He also polished all his armour although this was mostly met with Arthur yelling in disgust and shouting a lot. Prat.
Arthur sighed, probably in gratitude as he picked up Merlin's latest gift off the floor.
"George, put this dead rat in with the rubbish."
Ah, the hall of rubbish!
Where Arthur put all Merlin's gifts on display.
See? Merlin was a good protector.
He helped Arthur put on his mantle by tugging on the strings and gnawing on the hem before following to the door.
Arthur quickly pushed him away with his foot.
"No Merlin. Bad. Stay here."
Merlin momentarily forgot himself and let out a long meow of protest.
"No! Stay! Idiotic cat!"
Gasp! He knew, Arthur knew!
Merlin froze and must have looked very fearful for the next thing he knew Arthur was scooping him up and scratching him between the ears, just the way he liked it. He soon started purring.
Arthur chuckled and planted a kiss on one of Merlin's flickering ears.
"Don't worry, I'll protect you. Idiot."