Suggested prompt from tumblr. This is part of the merPhantom meets merDanny thing from chapter 8.

Under the Sea
Part II

Danny woke up, still feeling strange. He felt a little better than he had the last time he'd woken up, to be honest. But not one hundred percent better. Not yet. He was still…trapped under the ocean as a merman. With only his best friend knowing what happened to him. Right. Great way to start the morning.

Thankfully Danny came to find Phantom was still resting, curled over him and sandwiching his smaller figure into the surprisingly supportive sand. It was because Phantom was still draped protectively over him that Danny didn't have the heart to freak out too much, despite being a human stuck in a merman's body.

What did on my summer vacation was…'

Danny sighed softly to himself and without thinking, wrapped his arms round Phantom's torso a bit tighter and nosed under the merman's tan chin. He was careful to avoid touching Phantom's sensitive gills, and was content with simply watching the thin, soft gray skin flaps as they fanned and pressed in tandem with the merman's breathing. Despite his cautiousness, Phantom still murred in his sleep and Danny felt little talons slide over his skin and scaly back. Phantom fell back into sleep, and Danny decided he didn't have to wake Phantom up just yet, did he? No, he could let Phantom lie for just a little longer.

It would give Danny time to think, at the very least.

Time to worry. Because that's all he seemed to be doing right now, worrying. What would happen to him? How would he get out of this mess? Perhaps more importantly, how would he survive long enough too able to get back into being a human? Danny may swim with them and know one intimately (biblically, might be the better term,) but that didn't mean he knew the first thing about living under water. In this fish eat fish world, how much of a chance did he have on his own? He had to eat like them, move like them. God he was a sitting duck like this. Completely unknowledgeable, a total liability to Phantom—

That's right, Phantom. Who, on a good day, practically sat on top of him to keep all others away. Now that he was this much more pathetic and unskilled as a merman, Danny wondered if Phantom's protective instinct would get that much stronger.

'Or, maybe he'll dump your sorry, scaly ass the second he realizes you're a mistake as a human and one of his own. What do you even bring to the table in this relationship, honestly Fenton.' Danny's mind thought treacherously.

Danny grumbled, his head frills flattened back into his waving hair as the sour mood settled on him. It only made him press his body closer to Phantom's, who gave a sleepy grunt and started waking up. Danny winced when he felt the merman's breathing pattern change.

"Erh, sorry," Danny whispered, "G-go back to sleep—"

"No, it's fine Minnow." Phantom seemed to remember the events from yesterday. He didn't act surprised or shocked at all to recall his human was now down in the ocean with him and very much not a human except for half.

"I slept in anyway." Phantom admitted, gently shimmying back to stretch and shake his long body out. When he finished, he swung his tail back over Danny's and smiled fondly at him.

"Wait, really?" Danny blinked up at him in surprise.

"Mhm. I'm normally awake an hour before the sun rises. Better hunting." Phantom supplied when he saw the clueless look on the ex-human's face.

"Oh. S-sorry…" And here he was, clinging to the merman like a limpet and Phantom was probably starving. Come to think of it…Danny was really hungry too. The thought of what he would have to eat unsettled his stomach and frazzled his nerves, so he shoved away the only slightly annoying hunger pains in his stomach. Or did he have two now…?

Ah, God, this was all so confusing and new a-and terrifying.

Phantom must have caught the dread and worry that was coursing through him, because immediately the merman was all over him again, pulling him affectionately close and crooning reassuringly.

"Do not apologize. Are you alright?" The merman questioned, half answering his inquiry with wandering hands that gently felt and roamed along the mer's side and shoulders, up to his head fans. They flicked instinctively out of the way of those dangerous talons, and Danny just mumbled something nondescript and shrunk down sheepishly.

"M…Minnow? Danny?" Phantom tried when all Danny did was try to burrow deeper into his hold and the sand. Danny's tail flopped in distress and unconsciously tried curled round Phantom's black one.

"I—I'm fine!" It came out as little more than a squeak. Danny looked positively horrified at the noise, but Phantom chirruped back before switching to words Danny understood rather than felt their meaning. The chirrup was meant to soothe and calm, and so were Phantom's next words.

"…Danny. You are not okay, do not try and lie to me." The merman sounded faintly amused, "Your frills tell the real story."

"Y-you…you can tell that I'm—?"

"I can, Minnow. Merfolk have developed senses far beyond your human ones, remember?"

The smaller blue mer blushed and swallowed.

"It's just," Danny started lamely. "I'm really…scared, Phantom." He admitted softly, actually pulling back a little on the cavern floor, glancing uneasily at the shore sloping upward to the surface world.

The merman nodded at this. He knew, of course. This really only served to embarrass Danny further. Of course Phantom knew, nothing was ever that easy in Danny's life. He just really wanted Phantom to be proud of him, dammit, was that too much to ask?

He tried explaining how he felt about his current situation, wondering just when it was Phantom had started rubbing his hip just above his pectoral fin.

"I don't know why or how I'm like this, and more importantly I don't even know how I'm going to get through this whole fiasco. I don't know how to eat, or talk or act like a merperson."

Phantom looked rather surprised by that, and once he hid his shock better the merman spoke up.

"You will get through this just fine, Minnow. Why wouldn't you?" Something seemed to dawn on the merman, and Phantom actually frowned a little.

"Did you think I would you leave you when you needed me most?"

"Er…"

"I maybe a monster. But I am not evil, Minnow. Wicked certainly, but not, not to you. I'd rather get swallow a hundred hooks before I let something happen to you, especially if I could have prevented it."

Well, what are you supposed to say to that?

Danny bit his lip and looked sheepishly away, feeling vaguely chastised.

"It's just, it's a lot to ask for you to have to look after and teach me. It's probably dangerous, too."

"In these waters? Few things are more dangerous than me, Minnow. No one will touch what belongs to me." The longer merman grinned dangerously with that double set of fangs, the four sharp tips showing. It's little more than a crude gnash of his teeth with spread lips, but to Danny it's more reassuring than if God himself had appeared before them.

"But I don't even know where to begin, Phantom." Danny bemoaned. "How to be…what you are. And there's no way I'll ever be as good or as convincing as you."

"I don't expect you too. Have you been a mer your whole life, Minnow?" The merman spoke as he gently pushed off from the sand and rose. Danny sat up to stay by him, not even thinking. He just wanted to be close.

Sensing the oncoming logic, Danny admitted a little, "Well, no."

He noticed dimly Phantom was swimming, and that Danny was more or less following. The merman slipped into the tunnel that would take them back out into the ocean. On instinct, Danny grabbed hold of Phantom's tail gently but firmly. If Phantom noticed, he didn't comment on it, and let Danny cling to him as he swam.

"There you have it then. If I were to suddenly become human, and you found me on land, I'd likely be in worse shape than you."

"What do you mean?"

"Well, for starters, you know how to swim Danny. And you were doing it long before you met me, as a human. On some level, and you're already making progress with your tail. I have never walked a day in my life. I have a rudimentary level of speaking your language; even if I can understand it alright. Humans can eat most anything I hear. Fruits, plants, meat, fish and birds. I can eat only fish and some kelp."

"And bread, and cheese. That's what's in the pizza."

"Bread, cheese, and fish. Not a very wide selection, hmm Minnow?"

"Okay, okay I get it. But then…you really don't mind teaching me?"

Phantom's first answer was a fond, encouraging smile as he gently pulled Danny up out of tunnel out into the open ocean. His second was,

"I will teach you ride the currents and hunt for food, Minnow. I have no problem getting food for two. Besides," The merman was swimming oh so close to him, graceful hip fins brushing the little mer's sides and guiding him with all the instance of a mother hen handling her chicks.

"You've hunted for me many times, and hardly ate yourself." Phantom pointed out with an amused chuckle.

"I did?" Danny asked dumbly. "When?"

"The pyza, Minnow, the pyza! With those delectable, juicy anchovies and that warm gooey cheese." The merman licked his lips and purred at the very thought of the food, and with a rattle of scales he took off and swam deeper, out into the reef.

Danny startled and clumsily swam after him. He was just getting the hang of swimming with a tail instead of two legs that split, but he surprisingly felt tired. Still? He'd slept all night! And even late into the morning—Phantom had said HE woke up early in fact. So Danny should try to be like that, he supposed.

And his stomach was gurgling once in a while. Increasingly more so, especially after he'd started moving.

'Swimming uses so much energy…oh. I wonder if that explains why I feel like I haven't eaten in days?' But the thought of food down here only made his stomach lurch uncomfortably.

As if sensing his hunger—and maybe Phantom could—the merman brightly asked what he preferred for his morning meal. All it took was one memory of seeing a dead fish on Amity Beach with flies buzzing around its swollen eye, and Danny knew he couldn't eat if he tried.

"Actually, Phantom, I uh, I already ate, before I can down here. So you can hunt for yourself, and I'll catch you on the next meal!" Danny grinned, hoping his fake smile looked believable enough to Phantom. Who spun in a lazy arc to look at him in surprise.

"You have? Surely you must be hungry, my little minnow," He hung in the water, so when Danny finally wobbled to his side, Phantom could dip and brush against him like a happy cat.

"Ah, nope. I'm really not. Couldn't eat a bite!" Danny managed. "But I will be hungry in a few hours. You know us humans; we have weird eating hours, remember?"

"Mhm." Phantom conceded to that last statement, but still kept glancing an unsure look at the boy.

Danny pressed on though, distracting the merman by asking questions. Anything he could think of, though they finally landed on the ever important topic of swimming.

As they swam along over and beside the drop off in front of the reef, Phantom occasionally swooped and snapped up a medium sized fish with his jaws. Danny observed, despite feeling sick to his stomach as he watched the fish thrash until Phantom's jaws sunk his sharp teeth deep into his flesh and killed it. The smallest ones he swallowed whole, the bigger ones he munched and tried to offer, at least twice, to Danny. And every time he did, Danny shook his head and declined it with increasing fervor. Danny coughed when ever his stomach growled, and told Phantom it was because he wasn't used to breathing with gills. (Which was true.) The problem was, as the hours dragged on and the sun was about to set, Danny felt stranger and stranger.

Mostly light-headed, and queasy. Feeble. Which he figured was because of the fact he didn't want to eat. Not that it was because he hadn't eaten for technically, an undeterred amount of time. It could have been before he was changed. It could have been two days, he had no way of knowing the date or time down here.

Feeling wearier and heavier with each passing second, Danny swam closer and under Phantom's fanned pectoral fin a bit, as if the merman could protect him from his body's ever weakening state. They were swimming several hundred feet over the black ocean, which from Danny's point of view looked bottomless. He knew for a fact there was a chasm not too far from them, deeper than even he or Phantom could see. Nothing good lived down there.

Finally, when the little blinking stars at the edges of his vision were impossible to ignore, Danny could stay quiet no longer.

"Phantom?" Danny moaned, voice weak. He wasn't sure Phantom even heard him. The merman was currently explaining the social system and how their bartering structure worked. Before Danny was grateful he was able to distract the merman. Now he felt perhaps this wasn't such a good idea.

God, he was so tired…

"Minnow?"

"I don't feel…so good. M'kinda…" He wanted to say tired, but it came out as a soft groan as his stomach seized angrily again, somehow crippling his voice.

And with that, Danny's strength left him. Dizzy and exhausted, his fins went lax, his tail went off balance. As his tail went, so did the rest of him. He dropped, sinking like a stone, pulled into a strong current as his eyes fluttered. Disoriented and confused, the human could only tumble down into deeper, stronger currents.

"Danny!"

He felt himself sinking, and it was scary. What was even worse was as much as he wanted to fight the sinking; his body couldn't seem to answer his brain at all. He hadn't eaten, and no food meant no energy. And no energy meant his body was shutting down to protect itself. All his fins, his tail, his new found senses, and here he was: passing out and falling toward the bottom of the ocean!? Merman or not, the pressure down there would eventually get to him, crushing him. He'd die. Despite this horrifying realization, Danny's eyed fluttered closed, his vision waning as he sank into the dark depths.

There was a familiar shriek overhead, and he heard it dimly.

Phantom dived after him, teeth flashing as he grabbed hold of the smaller mer by the scruff. His skin was apparently much tougher, because it didn't hurt at all. Danny's body instinctively went limp, and the merman hauled him higher, only letting go with his teeth when he had his arms round the once human's torso. Phantom swam, hip fins beating laboriously, signaling his urgency to move them both as fast as he possibly could.

They rose above the drop off ledge and Phantom leveled out, lowering the slack form of his semiconscious mate to the sea floor among a soft bed of some sea sponges. No one else was around, but Phantom was barely noticing anything other than the paleness of Danny's cheeks or the way he was breathing so labored. His head lolled, black hair shifting in the gentle current as Phantom hovered over him, whining deep in his throat.

The merman growled as he inspected further and became aware of the problem.

"You liar." He hissed, pushing off the floor more forcefully than necessary and began casting around. "You promised me you weren't hungry." But his anger was more or less at himself, and if Danny wasn't mostly unconscious Phantom probably wouldn't have used such a livid tone on the boy.

His head frills flicked and fanned every which way, until he decided on a course of action and streak in a seemingly random direction, tail undulating like mad.

The next thing Danny knew, something was being pushed past his lips, and deep into his mouth. He swallowed on instinct, teeth half chewing and tongue moving to get the flavor of whatever it was he was swallowing.

Slimy. Chilly. Slippery. Rubbery.

It was a revolting texture but the taste was almost…enjoyable. The second after he thought this, Danny's humanity reared its ugly head and basically he thought 'what the fuck?'

Some hidden, deep seated hunger pushed aside all thought once more and he swallowed the hunk of flesh. It slid down his throat, into his hollow stomach. Before he could get his wits or miss the sensation of eating more was being offered to his lips, and he took it without thinking, raking the soft form right off something hard and rather sharp at the end.

There was a gentle chuckle at his eagerness to scrap the bone clean, a noise that made his frills almost stand on end. Danny weakly opened his eyes, vision sharpening to reveal Phantom leaning over him, in such a way Danny could only figure out that his head must be in the merman's lap.

"Ph'n…" He slurred, still with a mouthful of food. He gulped it down, gasping softly. The accompanying weight in his stomach felt so good he was almost light-headed from the pleasure of having something substantial in his stomach.

"It's alright Minnow. Just trust me." Phantom shushed, and Danny couldn't remember a time he heard the merman speak so tenderly. So Danny relaxed obediently, watching Phantom lift a fish carcass toward him, its side gone and several ribs exposed.

The disgusting sight slammed Danny into over drive and he wriggled free with a shriek, forgetting any pleasantness the previous hunks had given him.

"G-gross!" He spluttered, trying to wipe his tongue on his arm as the flavor tried to stick to his taste buds.

"Danny—"

"I, I can't eat that!" Danny moaned, even as he swayed woozily from sitting up to fast and getting a head rush.

"It's only flatfish, Minnow." Phantom tried to soothe, lifting up after him. Danny blanched, staring at the soulless eyes of the dead fish. Looking closer he saw teeth marks in its top, and saw a brown scale stuck to Phantom's lip.

"It's, we call it flounder…" Danny commented distantly. But his will against eating the fish was dying down as he realized Phantom had hunted it for him, brought it to him, and had been hand feeding him. Not to mention dragged him up after he'd fallen past the drop off. Talk about dedicated.

"Why can't you eat it, Danny?" Phantom asked patiently.

"It's just—it's so unpleasant, dude! Phantom, humans, they cook their food before they eat it! And they strip away everything…except what they're going to eat! Like eyes, scales, fins, bones and o-organs…" He stared at what he thought was some intestines hanging out, but how could he know? Oh, god. Danny felt sick all over again.

Phantom blinked, considering this a moment.

"So you are left with a hunk of muscle? That has been cooked? You are taking the whole animal away, and wasting so much. Not to mention the disrespect to the creature!"

"H-huh?" Danny's mind moved elsewhere, or at least to the topic at…er….in, Phantom's hand. The merman stared at him evenly and calmly went on to explain,

"I thank my meals, for every moment I can feed from their remains. Then I dispose of what I cannot eat, or offer it to something that I know can. There is always something for everyone. And it is disrespectful of the hunter to not appreciate every bit of their catch that they can. Neptune did not put us in this sea to have us waste what opportunities he gives us."

Danny stared, hands lowering as he listened. He was speechless, for a moment.

"That makes…a lot of sense." He murmured, glancing warily at the fish carcass. Phantom saw his resolve weakening and pressed forward, voice low and earnest.

"I hunted this flatfish for you, my precious Minnow. Please eat what you can stomach of it, and get your strength back." Phantom spoke softly, holding the body out.

"I wish only for your health. And just now, when you fainted…you scared me. Very much."

Danny quietly took the fish after that statement. Phantom had never once admitted or even shown fear in all the months he'd known his best friend. But for Danny, he put it out in the open, and that admittance made Danny loved Phantom that much harder. The merman was watching him so seriously, so compassionately Danny decided maybe he could eat raw fish after all.

For Phantom, he would. For his merman, he had to survive.