Water filled his ears, his eyes, his mouth- and Harry came to the fearful realisation that he was, in fact, drowning.

He grappled fitfully under the water, clawing blindly around him- trying with all his might to grab onto something, anything. of course, there was nothing to ground him, and the water fell uselessly through his fingers.

Bubbles filtered out from his nose as the air began to slowly but surely leave his lungs. He kicked his legs, but they flopped about in the water- pointless in the face of swimming.

Terror seized him by the throat, and his heart rattled in his chest. His head swam; dizzy and disorientated- Harry no longer new which way was up or down.

'Oh god' Harry thought, as fear seeped into his bones, drawing in from all corners. 'This is it. I'm dying'

Memories long repressed flooded his mind like a movie reel, playing in a loop- again and again he was forced to relive his childhood fears.

There was water; water everywhere.

Water. Dudley pushing him into the duck pond when he was three, uncle vernon furiously dragging him out by the scruff of his shirt.
Water. A bucket-full thrown into his cupboard one morning, startling him awake.
Water. Dudley and his friends holding him under the water fountain at the park, laughing when he struggled against the many hands pinning him in place.
Water. Aunt Petunia's bony hands forcing his head under the sink faucet as an old, scratchy dish scrub worked clumps of dirt and leaves out of his messy hair.

Water. Now, as he grappled in the Lake, unable to swim a single stroke.

Ringing filled his ears as he sunk deeper into the shallows of the lake. His back hit the cracked bottom of the lake floor; the clay beds, causing dirt to spring free- enveloping him in a a murky cloud of filth.

Seaweed snaked around his legs- sharp and thorny plants slicing into his calves as he kicked and wriggled for freedom.

He gave one last scream for help; but all that emerged from his lips was a short, tinny noise, and a small stream of bubbles. He watched the bubbles as they floated to the surface, and wondered how they managed it so effortlessly.

He spotted movement from the corner of his eye; something large and fast, glinting in the sun as it hurtled It's way through the water. But harry's attention was wavering- as was his ability to stay awake.

His lungs burned with the need for oxygen, and Harry couldn't take it any longer- his body finally gave in to demand with a gasp. Hand-fulls of water seeped into his starving lungs.

Suddenly, A pair of strong arms seized him around the middle; and pulled him upwards through the water.

Harry lost consciousness before he even broke the surface.

—————————————————————————————————


The lone merman observed quietly and unseen as the Slytherin boys tossed potter into the lake, all three of them watching with glee as he sank like a rock into the murky shallows.

The three boys onshore then proceeded to grab potters discarded belongings and scarper, running back through the trees and out of sight- laughing as they went.

After watching his students retreat, Snape turned his scrutinising gaze to the shallows. He observed the waters surface with a long, fixed stare, waiting for the potter boy to breach it and crawl his way out the lake- waterlogged and ready to throw a typical Potter-tantrum when finding all his belongings had been stolen.

Except that moment never came.

The water went still, and a deeply disturbing feeling washed over the merman. A sharp, unsettling pain shot through his abdomen; a gut instinct telling him something wasn't quite right here.

He ignored it.

Instead, he was content to stare at the spot of water potter had disappeared under, watching. Waiting. Just for a little longer at least.

But the lake remained unmoving for a long while, far too long for anyone to be comfortable with- especially when knowing that a student was currently below those waters.

'What in the world is that wretched boy doing?' The potions master thought with a snarl, gills quivering uncomfortably as he exhaled a short puff of angry air. 'too lazy to use your legs, Potter?'

Unsettled, The merman swished his tail to-and-fro where he remained, floating, watching for any signs of the Boy. Long sprouts of seaweed tickled at his scales, sticking to his tail and wriggling in between his fin rays- making him overwhelmed and uncomfortable. The Weeds that grew here this time of year could be quite tough to get around when tangled up in them.

"Perhaps-" Severus mused quietly, a small, niggling feeling of dread making his words wobble.

'How ridiculous' he mentally cut in with a scoff, 'I wouldn't put it past Potter to hoax his own drowning to try and gain some attention.'

He smirked, shark-like teeth glinting through blue lips.

'As soon as he realises no one is giving him the time of day, he'll pop right back up to the surface.' And that was that.

Snape carefully retrieved his ingredients from the rock, before taking leave. He turned, ready to dive back into the murky depths below- when movement caught his attention. He grinned wryly.

'And cue Potter'

Small Bubbles broke the surface; Not the boy.

Snape Bolted.

Discarding the plants in his hands, Snape dived down into the water, swimming as fast as his tail-fin could carry him. The sharp plants and thorny seaweed snagged at his scales, scratching at his arms- but he pushed on through them with vigorous energy.

The shallows drew closer, and Snape searched tirelessly through the plentiful, bushy seaweed stalks that emerged from the viscous clay beds.

'Potter, where are you?'

'There!'. He spotted the boy, half conscious and caught up in a thick nest of thorny plantation- Snape dove for him. With careful but urgent hands, he tugged, pulling the boy free from the sharp foliage; cutting them both in the process.

The boy gave a feeble cry, bubbles teaming from his mouth and nose, before going slack in his arms.

Snape pulled them upwards, breaching the surface;

And headed for shore.

———————————————————————

Harry came to his senses slowly, only managing to drag himself out of the haze that nested at the front of his mind when he felt a short, pesky stinging sensation on his left leg. 'Ouch'.

The prickly touch became sharper, till it was almost unbearable, and Harry grunted in pain. He willed his heavy eyelids open;

only to wish he'd kept them closed.

His mouth hung open, astonished and petrified. 'What in the world is that'

Harry's legs -half dipped in the shallows of the lake, where the rocks and pebbles were just visible still- were being tended to by a- a...well, he didn't quite know what it was exactly. Only that it was horrifying to look at.

It was perched by Harry's feet, fully engrossed in detangling the boys limbs from the thick thorny weeds still tightly wrapped round the bottom half of Harry's body - So much so, that it had yet to notice Harry watching, wide eyed and completely speechless.

At first glance, Harry thought it was a man, a very alien-looking one at that. But then, when he slowly and carefully propped himself up on his elbows to get a better look, Harry realised he was very, very wrong.

For whilst the top half of the 'things' body could well and truly pass for a man (if you squinted, that is), the bottom half could, in fact, not. Because below the creatures hips, we're legs would normally be found; was a fish tail.

Just above the waistline, sickly pale skin met with deep, dappled blue scales, so dark in colour that they quite nearly became lost in the lake water. Harry had to focus his eyes to see the inky scales, only managing to catch glimpses of them when the water rolled over the 'things' body.

A large, black tail fin stood poised out of the water, swishing lightly back and forth over their heads. Light shone through the semi-translucent fin, creating a window for Harry to gaze at the tens of individual fin-rays, as well as the large tail-bone in the middle, linking to the creatures spine. 'Ew' he couldn't help but grimace, for imagine if humans had see-through skin and were able to see to their tail-bones.

Harry glanced back to his legs, more specifically, the hands currently touching his legs. Pale blue fingertips, equipped with long, black nails, that sharpened to a point- sliced through a very thick stalk of seaweed with seemingly no effort, freeing up Harry's leg to a more comfortable level. Harry internally sighed with relief, his leg no longer felt like it was suffocating. It was a marvellous contrast; The creature, with large bony hands, and even larger clawed-fingers, was taking effort to be careful when dealing with Harry's tortured little legs. The hands flexed, and Harry quite nearly gagged at the sight; webbed hands.

Harry's eyes then travelled up towards the creatures face, but the "fish-man" ( at least, harry thought it was a man) was hunched low over the boys legs, sorely fixated on his current task- that Harry couldn't see anything past the long curtains of dark hair. So Harry let it be, and stopped prying- he'd already seen enough of the strange creature to last him a lifetime, he was sure of that.

The fish-man, as gentle as he was trying to be, struggled with the last vine tangled round the boy's leg; and in his effort, pulled too hard.

Thorns pierced the underside of Harry's leg, eliciting a short gasp from the boy.

Harry clamped a hand over his mouth, but it was too late. The noise had startled the creature;

It's head snapped up to look at the boy, and through dark ringlets of black hair Harry could make out a pair of black-slitted eyes glaring up at him, before thin blue lips parted- giving Harry the perfect view of a set of razor sharp teeth.

Harry promptly opened his mouth; and screamed.

———————————————————————

Snape had not long dragged Potter up onto the shore- it was a challenging task, might he add, as he had to be careful and keep himself still somewhat immersed in the water- when he noticed that the boy wasn't breathing.

'Damn it' he thought with a growl, before long slender fingers frantically checked the boy's neck for a pulse.

The tender thump thump of the boy heart could be felt underneath his fingertips, and Snape quite nearly sagged with relief- before briskly jumping back into motion.

He quickly, albeit carefully, manoeuvred Potter into the recovery position, unhinging the boy's jaw and giving a quick check down his throat to see if there was a blockage. None.

Finding no water blocked in the throat area, Snape blanched, turning an even more horrid shade of white.

The problem wasn't the boys throat, but his *lungs*.

Snape grimaced. He *really* didn't want to have to perform CPR on a *Potter*.

With water having already entered the lungs, And with the boy *still* not breathing- Snape has no choice but to take matters into his own hands. Quite *literally*.

"I really mustn't" he mumbled to himself, torn. A voice in the back of his head countered him- 'you don't have a choice' it said, and Severus gritted his teeth, because it was right. 'The boy will surely die if you do nothing'.

After a small internal battle with himself, snape finally relented. He cupped his webbed hands so that they were shaped like little bowls, and in one fell scooping motion, collected a small handful of water from the lake.

As the water left the lake surface its dynamics began to change. It didn't slip through the mer-mans fingers or roll off the edges of his hand, but stayed perfectly still; forming an ideal dome-like shape. Almost as if it had changed state, becoming semi-solid in the space of a few seconds.

Obsidian eyes glanced at the unconscious boy, before flickering back to the pocket of water clutched in the merman's grasp. A low, guttural whining noise began to emerge from the back of his throat. It was a long, damaged noise, that sounded almost like a sob to human ears- albeit a strained one, like it took a lot of effort and energy to make.

Suddenly, A few tears rolled off the creatures cheeks, before dropping into the dome, fizzing and swirling about in the small body of water before quickly dispersing.

He looked at the boy a second time, before staring deeply into the bubble of water in his webbed clutches. The merman spotted his own reflection glistening back up at him. He sighed.

With his free hand, Snape lifted the boy's sopping school shirt, before massaging the water over his chest area, particularly the spot where his lungs would be- working silently and with precision.

The water at his fingertips glowed, a bright iridescent light shimmered from his hand and engulfed the boy's body, before disappearing as quickly as it came.

Silence. Snape waited with bated breath.

A mere few seconds later (which felt a lot longer for the half-man), a gurgling noise emitted from the boy's throat, before he choked- Water spewing from his mouth in sharp, hacking coughs.

Green emeralds peeked up at him through half lidded eyes, and Snape froze in fear. The boy looked at him for a long moment, wheezing, before his eyes began rolling about unseeingly in his head- and Snape let out the breath he was holding. The boy was very much out of it, and thankfully wouldn't remember this.

As quickly as he woke, Potter fell unconscious again- his breath even and no longer struggled- and Snape was able to get back to work without worry.

He took one hard look at the boy's legs, before his face twisted into an ugly scowl.

Potter's legs were a sight for sore eyes. The entire lower half of his body was tangled up in thick, sharp tendrils of seaweed, Trapping his legs, which were slowly becoming soaked with blood.

Snape peeked underneath the seaweed stalks to find nasty little gashes where the plants had sliced into his legs, no doubt during Potters struggle to swim. His trousers were completely torn, useless- the boy would have to order new ones, or at least borrow some from the "lost property" department for the time being.

He began to slowly unravel the boy's legs from the weeds, being sure to be both attentive and cautious as possible, if Potter woke up for a second time there'd be no guarantee he'd fall back asleep again. Snape had been lucky he'd done so the first time round.

He started with the ankles, unwinding the tricky little vines from the boy's legs, occasionally checking to see if he would stir. The child remained motionless, and the only time He'd show any kind of response to the merman's actions, was when Snape would accidentally snag his sensitive skin with a sharp underside of the plant- eliciting a short noise of discomfort, before silence once more.

It carried on like this for a while; unwinding, re-winding, and unwinding again. Nothing but the sound of the water lapping at the shore, and Potters soft breathing to lull him into a methodical pace.

Snape soon became immersed in his task, so immersed in fact that after a mere few minutes of working, he no longer registered his surroundings. The sounds of the water withered, and scattered into the silence, and Potters small, short breaths dissolved completely.

That is, Until, he pulled at a rather troublesome weed- and heard a soft gasp beside him.

He looked up, startled, his eyes narrowing at his own irresponsibility. He bared his teeth in annoyance;

For the Potter boy was awake. Wide awake.


——-

Harry had barely gotten a good scream out before a large, silky webbed hand clamped over his mouth, muffling his cry.

"Shh!" The creature made a hissing noise at him, as it's other hand came up to wrap around his shoulder, pinning him into place despite his wild struggling.

Harry stilled at the command. His eyes widened to the size of dinner plates, and his heart pounded in his chest. It almost stopped beating completely when the thing suddenly leaned in and spoke.

"You certainly have a way of thanking people who just saved you're life" It growled, black eyes shining.

Harry visibly shook at the creatures voice. It was low, gravelly- and sounded utterly inhuman. A strange noise vibrated from the back of its throat as it spoke, an almost metallic sound; like rubbing two copper pennies together.

With Harry rendered speechless, (in the physical sense too) he had no choice but to sit and listen in fear as the creature continued, "I'd really advise you not to scream: I dragged you out of that lake, don't think I wont throw you back in"

It was a poor attempt of a threat on Snape's part, most certainly not one of his best, but it seemed to do the trick- Harry was terrified.

Harry watched as the merman's gaze flickered back and forth, searching their surroundings, before leaning closer, hand still pressed firmly against Harry's mouth.

"Now" It spoke, voice barely above a whisper, "I'm going to remove my hand, and 'you'" He punctuated the last word with a short jab to the boy's sternum with his free hand. "Are Not. Going.To. Scream. Are we understood, boy?"

Harry shuddered, both from the cold air, his wet clothes, and the fact that a freaking 'merman' was currently threatening to kill him: before nodding wildly.

Obsidian eyes narrowed at him, before the scaly hand was retracted from the boy's face.

"Good"

Harry breathes out through his nose, long and hard- trying to calm his racing nerves. His eyes never left the half-man, who in return was levelling him with a hard stare. Harry scooted away slightly, and the creature got the message- it moved further back into the water.

"Remain calm" it said, and without warning, seized Harry's left leg. The boy flinched, but held his tongue.

With the same previous method, the mer-creature began cupping water in its hands, choking and weeping till it produced enough tears, before dousing the boy's legs with the tear-infused water. Harry watched, both amazed and petrified, as his bloody calves began to glow under the beasts hands. One by one, each cut began to sew itself up- till nothing remained but a few faint lines.

The mer-man did the same for his other leg, and Harry tried to keep his gasps of pain to a minimum. As incredible as the healing process was to watch, it still hurt terribly.

The creature was soon finished; A long, heavy silence filled the air around them.

Harry opened and closed his mouth several times, trying to find his words. "Wh-How-"

The creature gave him a very unimpressed look, eyes squinted and gills quivering on its neck as it huffed impatiently at him.

"What-" He eventually tried, but just as he'd found his voice again, it appeared that the fish-man had too.

"I'll spare you the energy of mustering up some gratitude" it began, voice dull and void of emotion- though Harry was unsure whether sea-creatures could even have emotions like humans. "and say 'your welcome', and be on my way"

It turned, ready to disappear into the deep black underworld of the lake.

"Wait!" Harry called as he sat up fully, stopping the half-man in its tracks. "Wait. Please"

The merman looked over his shoulder at him, and Harry shrunk back slightly from the piercing stare he was receiving. Nevertheless, he asked. "What are you?"

The half-man scowled, facing him, and Harry quickly rephrased his question. "I mean, who are you?"

Snape blanched, wishing he'd fled sooner. In fact, he wished the boy had stayed unconscious. Then he wouldn't have to deal with questions he didn't want to answer. Or rather, he didn't know how to answer. No one was supposed to know about this, and up until now, no one did.

Harry, having not received an answer and unaware of the internal struggle the mer-creature was currently having with himself, carried on talking- hoping that the fish-man would answer at least one of his questions.

"I'm Harry" he said, pointing to his own chest. He then pointed at the creature, who followed his hand with its deep-black eyes. "What's your name?"

Harry didn't realise even that question was difficult for the man to answer. 'He can't know' his mind screamed at him, 'he mustn't know who you are'.

Of course, Snape was left with no choice but to conceal his identity somehow, even if that meant coming up with an alias. And He had to be quick about it.

He was silent for a long moment, and Harry grew concerned that he'd overstepped a line. Was it rude to ask a mermaid their name?

Eventually the sea-creature spoke. His answer was one worded, but Harry was appeased nonetheless.

"Hydrus" He said, and a black tongue emerged from his mouth to swipe nervously at chapped, blue lips.

'Ah, Sea-serpent. Well done Severus' the voice in his head mocked. 'Not at all obvious'.

However, the boy remained unaware. He repeated the name, and it sounded a lot more foreign on his tongue than it did on the merman's. He then gave a tentative smile, before looking down at his healed legs.

"That's your name?" He asked, still smiling. "It's...nice"

It wasn't nice at all, and Snape didn't pick it to be seen as so. No, he picked it because he was stupid and put on the spot- and thus decided to go with the Latin equivalent of "water snake".

"Thank you" potter suddenly spoke, and Snape's attention was drawn to him once again. The boy was looking at him, trying to transfer how deeply he meant what he said with his eyes, of which were glowing with profound gratitude. "You saved my life"

Snape snorted, and to think the boy had been scared of the mere sight of him moments before. Did all it take was someone's name for the boy to suddenly trust?

Nevertheless He nodded, acknowledging the boy's thanks, albeit awkwardly. "Yes, well. Be that as it may, I still need a favour from you in return"

The boy's eyebrows rose high into his hairline, resting right where his scar was, hidden underneath his messy, wet fringe. He wordlessly pointed to himself, before grinning when the merman (sighing) nodded his head. Snape leaned in closer, and the boy listened with rapt attention as he spoke low and with warning.

"Don't tell anyone about what you've seen today. Not. A. Soul”

"But Why?" Harry asked curiously, wincing at the stern look the creature gave him in return.

'Think Severus, and fast'. He lapped at his chapped lips once more, before answering the boy, careful not to mess up any further. Well, the worst he could do at this point would be to outright say 'because I'm your potions professor, and if anyone found out what I was I'd be well and truly ruined'.

So instead, he said, "Our 'kind' prefer not to be involved with humans. Your people can often be very dangerous in the face of what they don't understand. It can get violent very quickly, and the mer-people of this Lake are very proud individuals who aren't afraid to-"

"Mer-'people'? There's more of you?"

"That is irrelevant" The merman snapped impatiently, and watched as Harry recoiled. He breathed deeply through his nose to calm himself. "What matters most is your word- no running off and telling people of what you seen in the Lake. Not even the- 'your' headmaster. Is that understood?"

The boy in question chewed his lip, pondering the request, and Snape held his breath. Eventually he nodded. "Don't worry-"



"-Your secret’s safe with me"