The existence of beings that had been considered myths had only been officially confirmed a few hundred years ago, but the stories themselves went back thousands. Sirens, merfolk, the denizens that sank with Atlantis. Each exquisitely beautiful with gem coloured eyes, hair of various shades while being of silk like quality and a rainbow array of tail colours. Said to have voices that enchant all who hear.

And their favorite food was human flesh.

Teeth as sharp as any sharks, a body streamlined for great speed with a powerful tail to propel them through the water. And most importantly long razor sharp claws that had evolved to cut through man made steel.

That was why they were recognized as sentient beings. Not that they weren't. If you could meet one face to face and not be eaten you could have any kind of conversation you wished. Be it of the mundane or about philosophy. There were even those educated in the higher levels of education; like maths and sciences, though they were few as not many had the interest. But that was not the main reason they were considered sentient. They were considered so because humans could do nothing about their existence.

The merfolk lived in pods similar to dolphins, and were just as widely spread. Unlike dolphins, merfolk had no need for air and as such most when not hunting for humans or other mammals for food lived deep in the ocean depths. To even attempt to bomb them would cause massive tsunamis that would harm land dwellers. Anything done to the oceans to harm merfolk would also cause harm to humans. And as stated previously, merfolk had adapted to the fact that their favorite prey liked to encase themselves in giant metal structures when they had to travel through large bodies of water, so all ships and submarines were easily sinkable.

Because no permanent solution could be found instead the world acknowledged the existence of merfolk and set up rules to keep as many safe as possible.

The world's oceans and sea were painstakingly mapped for areas that merfolk frequented so the few ships in existence could try and avoid them. Things like cruise ships became a thing of the past when the first pleasure ship was sank and all crew and passengers devoured. And beaches not only had shark watch but 'beautiful unclothed humanesque being' watch. And 'merhunters' were looked on with disdain as those throwing away their lives.

However life moves on and tales of merfolk had been around far longer then the official recognition and the average person already knew of their existence long before hand. After all it was said the merfolk could come onto land and many had lost loved ones to the sirens of the sea. However they were not all lost due to being consumed for food, but also by falling in love.

Tales told of mermaidens coming onto land and enticing young men into bed. Who then would return to sea and the one left behind would attempt follow their loved one and drown in the process.

Or of the tales where young women would find handsome men on the shores, have a passionate night, then have the child go missing within the day of it's birth. How young mothers in their grief would try to regain their child and they too would drown in the attempt.

That was how it worked for years. Official ship transporters avoided the marked areas, however death by 'mersink' was considered just another hazard of the seas. And the regular folk passed down warnings to those who lived near the shores to be wary of one night stands with beautiful strangers.

That all changed with Charles zi Brittania the 98th emperor of the Holy Brittanian Empire. It was common knowledge that the emperors fifth 'wife' was a commoner. What isn't well known is that the Lady Marianne vi Brittania was found on the shores with no known background, with her wavy ebony hair, porcelain skin and lovely violet eyes. It was heavily suspected that young Marianne was one of the 'landed' merfolk, come to entice some random young man to give her a child so she could go back to sea.

However all suspicions were laid to rest as over the years she not only did not disappear, but she gave birth to a healthy baby boy, the eleventh prince Lelouch vi Brittania. Then a few years later a daughter, the seventeenth princess Nunnally vi Britannia. It was unheard of for one of the merfolk to not take their offspring back into the sea, so the Lady Marianne must have been just a regular commoner.

No mention was ever made of just how...off Lelouch and Nunnally were. After all when Lelouch was little and chewed on peoples fingers it was simply because he was teething. No one heard Marianne's gentle admonitions about not eating his half siblings yet, let them grow and get some meat on them first. How little sunshine Nunnally loved to get people to do things for her, it was just the royal charisma showing early not merfolk enchantments. How neither were squeamish around blood, ever. After all they were young royals showing the strength of character required of their positions.

And when neither really got along all that well with the rest of the royals, it was because their mother was a former commoner and that caused friction. It couldn't be because Lelouch and Nunnally felt they were surrounded not by family; as their pod was small consisting only of Marianne, Lelouch and Nunnally, but by livestock. It was at times fun to be around them, like it is fun to be around animals, but they were simply waiting for them to grow up and have enough meat to be eaten. Though Schneizel, Cornelia and Euphemia all showed promise of being good breed stock for other mers, so they might just lure them to the ocean instead. Have to keep adding new blood to the sea dwelling people right?

And when their mother was murdered and Lelouch confronted the Emperor, many assumed it was purely out of grief over his mother's death and sisters crippling. It wasn't. While grief was a major factor, without their mother they no longer had a supply of 'to be executed' criminals to feast on. The two feared for their survival as Nunnally's crippling meant only Lelouch could hunt and at their age human meat was necessary for proper growth. And no matter how their mother had tried to teach them that Charles was a 'special' human he remained to Lelouch and Nunnally just another human. A human who had threatened the pods survival, which was unforgivable.

Sent by air to Japan as hostages Lelouch feared he wouldn't be able to get Nunnally the proper nutrition that came with eating humans without putting the two of them in danger. Physically weak compared to the Kururugi child (and he always would be as, though his tail was strong, it being split into two spindly legs wasn't something he could overcome) but still considering him prey, the two fought constantly. Till slowly through interacting often they began to tentatively like each other, even enjoy the others company.

When one day Suzaku caught Lelouch in the lake completely transformed; tail an array of purples and blues, multiple fins small and large, claws a few inches long. He'd been hunting fish for himself and Nunnally (but mostly for Nunnally). Suzaku, instead of freaking out or running to tell his father or a guard, talked with Lelouch. After a long explanation, fielding a slew of questions and an emphasis on just how important human flesh was to young merfolk, Suzaku just nodded in acceptance. He later showed up with a few slabs of pilfered raw steaks, asking if it would help as he couldn't really get an actual human.

Lelouch thought he was finally beginning to understand what his mother meant by a 'special' human.

DLS here.

So this little one-shot has been an idea floating in my head for years so I thought I would finally write it down :)

It has been beta read by the awesome Kira31 so many thanks!