Author’s notes: In the Lost Tales we read that Telvido is one of Morgoth’s servants that played a major role in the story of Beren and Luthien. He is called the Prince of Cats without further information of his background. Later, Tolkien abandoned this character and one can only speculate of his fate.

Regarding Morgoth’s physical reaction to the cats, I followed this line, assuming that all corporal bodies have some flaws.

“By the time of the War of the Jewels, he was completely bound to his physical form.”
Morgoth's Ring, HoMe 10, Myths transformed.

Ailurophobia means “fear of cats”.

Ailurophobia

Like thunder and lightning he came upon the land, a Lord fierce and mighty, wielding the power of the heavens. He took residence in the Hells of Iron and called forth the creatures of darkness to serve him. With words sweet and false he enticed them, those that favoured all things dark. Sauron the Maia was among those who pledged his service to Melkor, out of love for cunning and deceit. But Sauron was not the only one that found the calling of Morgoth appealing.

In a time now lost in grief and sorrow, Telvido the Prince of Cats knelt before Melkor. And Melkor was pleased for he saw in this servant’s heart the shrewdness he himself favoured and the burning ambition to rule over Arda. He released to Telvido a vast part of his fortress to dwell in and ordered myriads of orcs to be placed under his command. So the Prince of Cats took residence in the dark depths of Angband; and his minions followed his trail.

~*~

In a room dark and cold, where black candles had long burned down, Morgoth rested his head upon his bed of marble and obsidian. Among dreams of fire and conquest, he stirred in his sleep and rolled onto his side. And there, between dreaming and waking, his eyes caught glimpse of a liquid movement across the stone floor of his chambers. Surprised, he reclined and opened his eyes to see the creature that dared to disturb the rest of Melkor.

In the dim light of the room, among the dancing shadows and the reflections of the fires of Angband, a slender form moved graciously. In every step a thick fur shone for a fleeting moment, making no sound in its path. Melkor assumed that this should be one of Telvido’s minions; one that the Prince of Cats had failed to instruct properly. Before he could react in any way against the intruder, the creature jumped on the bed and fixed its yellow eyes on Melkor’s face.

Curiosity overtook his irritation and he studied this strange animal. He had never met a similar creature and he eyed the black form suspiciously. It was covered by thick, black fur that provided it with a perfect cover in darkness. The animal raised its paw and licked it, a paw so soft that added to its stealth and noiseless movement. Then the creature raised its head and returned his inquisitive gaze. Melkor frowned. This beast showed nothing of the respect he expected from his subjects. It stared at him as if measuring him, with an intelligent sparkle in his yellow eyes that most of his servants lacked.

Melkor was still undecided on the usefulness of this animal, when it raised its hind leg and scratched its head, letting loose a cloud of dark fur.

Then the tingling started.

He had never felt anything similar, still unaccustomed with the traits of this corporal shape. Melkor rubbed his nose in a futile attempt to ameliorate the tingling under the curious stare of the creature. And then he sneezed. The animal arched his back and hissed and spat in the most disrespectful way. Then Melkor sneezed again. When he was able to open his eyes again, he saw that the creature had fled.

Tearful and furious, he rose from his bed. Telvido had a lot to answer for.

~*~

Over the coming weeks, Melkor wore a thick cloth over his face to keep his airways free of the fur that those creatures shed in abundance. Telvido had met his wrath and repented under the threat of the whips and the chains of the deep dungeons of Angband. But in time Telvido had managed to convince him that this was simply a passing malady; one that the essence of the Valar in him would soon overcome. His minions were competent spies; in the cover of darkness they could climb up any wall and sneak inside any building, silent and sly as no orc could ever be.

However, the creatures lacked any sign of discipline. They roamed the halls of Angband as if they ruled the place, sneaking into crypts and barracks, pestering on his obedient orcs. They seemed to be always hungry; Telvido swore that the cooks in his dungeons broke their backs over the stoves to provide for the cats. But his servants in the dragon hatcheries complained that the creatures were stalking the hatchlings and had already attempted to devour an egg.

Seated on his black throne, Melkor contemplated on the matter, greatly displeased. His werewolves had issued similar complaints, for the cats had taking a liking into harassing their cubs. And Melkor’s ailment seemed to be more persistent than Telvido had had him thinking at first. The creatures had found his sneezing to be a great source of amusement and climbed on his bed and throne and shoulders at any given moment. Their fur managed to creep in everywhere; his clothes, his mouth, his eyes. On numerous occasions he had walked in his chambers to find one comfortably napping on his pillow. Not long ago, one of their females had given birth on his robes and even his orcs cowered before the talons of the hissing female cat.

Whatever their qualities were, they were hardly worth the trouble they had brought with them.

Walking in this hall to find two of them copulating on his throne had been their final insult.

~*~

He could have killed him. He could have tortured him. He could have delivered his body to the Balrogs’ pits or the dragons’ lairs. But Melkor chose a different punishment for the servant who failed him. He banished him east of Angband where he would dwell with his only company this of his creatures.

In horror, he who called himself the Prince of Cats stared at the hungry eyes of his former minions.

We are hungry, they said.

Feed us, they demanded.

Our young are starving, they growled.

The last thing he saw was the flash of countless ivory fangs. The last thing he heard was the hiss as the felines leaped in the air. The last thing he felt was claws tearing his skin and rough tongues licking hungrily warm blood.

And nothing else was ever heard in Arda about Telvido, the Prince of Cats.