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Through Kelp Forests

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Tenzou’s fins fluttered as he slinked down a little in the tall kelp, peering through the lazily swaying fronds.

Kakashi watched over his genin in the waving seagrasses beyond, his book open in one hand, his slightly overlong tail swishing lazily. The genin were tangled in a knot, shouting, bright orange streamer-edged fins waggling and sticking out from a twist of sleek, pink tail before they twisted, tumbling through the water, and a dark mottled band came into sight instead.

It probably wasn’t training, exactly, Kakashi had probably elected to let them wear themselves out a bit when they had gone off target.

A yelp that verged more on pain than distress spilled from the writhing ball of young mers and Naruto froze, all his spines flaring outwards. Kakashi’s book was nowhere to be seen as he was suddenly there with them, interposing his tail to sleek down Naruto’s spines, pulling Sasuke away with one hand - his fangs were bared and his claws extended - and tucking Sakura against his side with the other.

The genin thrashed and wriggled, and Kakashi checked them all efficiently for injuries - as he did so he soothed them with gentle strokes until Naruto had relaxed his spines on his own, and the tense lines of Sasuke’s body eased, claws no longer poised to strike, and Sakura’s tail coiled into an easy spiral rather than a bristling arc.

Tenzou sighed, tail curling a little around one of the kelp stands. The others nearby leaned in towards him companionably and he ran his fingers through rippling leaves. He watched as Kakashi got the younglings organised again, and they began something that was almost a game even as it tested their reflexes and worked their muscles, building good habits, ones that would keep them safe in enemy territory, in battle.

Tenzou smiled a little, melancholy. He missed Kakashi, so much, and his heart ached watching the happy mess out in the little practise field.

The first time he had come across Kakashi with his young team training here it had been honestly in the line of duty. After that. . .

Well. Tenzou could spare some time from his duties, especially when he was heading out or more so when returning from his missions, and while he would never interrupt Kakashi or- or try to bring him back. . .

Tenzou missed him so, and at least seeing him like this . . . soothed that ache. A little.

Tenzou’s leafy fins rippled in the current and he leaned his head against a kelp frond, gills fluttering. Kakashi had his book out again, and Tenzou wondered if the genin realised how sharp his focus on them truly was as he read, tail twitching from time to time as he circled lazily around the outskirts of the field in which they were training. Playing.

It was time to go, Tenzou knew; when Kakashi approached the kelp forest at this end of the field, even with his attention fixed on his genin, he would sense Tenzou. He might or might not recognise him immediately, but the first reaction might very well be to a perceived threat - and if it wasn’t, then Tenzou still did not wish to disturb Kakashi.

In his new duties and the new phase of his life, away. . .

Tenzou swallowed thickly, gills trembling, and pulled himself free of the kelp, tearing his gaze away from Kakashi. He didn’t wish to try and impose himself in Kakashi’s new life, where there was no room for a broken mer with no past and no place outside his hidden duties.

No room for Tenzou.

Kakashi grinned, shooing his bratty little pups off after training, watching how they moved as they swam off and making a note to keep Sasuke from further straining his tail tomorrow, and increase the flexibility exercises he put Naruto through.

Sakura was flagging but the only way to build her endurance was to test it - even if pitting her against the boys in that respect was perhaps doing her a disservice. Kakashi sometimes felt exhausted watching them himself.

Perhaps he could set them to something less . . . destructive tomorrow, and work with Sakura on endurance exercises without them pushing in and causing . . . problems.

Kakashi debated the idea - and what trouble it might cause, because leaving Naruto and Sasuke with less than half his attention was always inviting disaster to some degree - as he made his way through the village alone, his book in front of his face. With a lifetime of practise, it was easy enough for Kakashi to avoid even the casual, friendly brushes of other mers’ tails that left him so on edge, even with his book blocking his field of vision and taking some of his attention. Less than people tended to assume.

He slipped into back pathways of his home village that few knew, narrow tunnels and half-hidden crevices, twisting and thrashing his tail. He squinted, putting his book away as he passed through a narrow stretch that almost scraped his hips - he wondered how some of the others fit through here; Kakashi was slender and his tail flexible, some of the others. . . - but brought it back out again immediately, and kept it out even as he passed way through the artificial blackness of another stretch of passageway.

He knew it was a subject of some debate among the ANBU, how he kept reading in such areas - and many had concluded that he merely faked it, either with his long familiarity with his books or by blatantly skipping. Kakashi smiled a little wryly and offered an idle thanks to his mother’s blood for his sharp vision even in such heavy darkness as he turned a page.

He put it away only once he was inside ANBU headquarters - where, he supposed, he should perhaps no longer be allowed, but no one had ever tried to keep him out or tell him to stop. Kakashi cocked his head, pausing as he opened the sealed door to the records room. Well. No one had tried seriously, anyway.

He considered the sighing reminders and little warnings he’d been given as . . . suggestions. He wriggled his tail in a lazy shrug and went to the new returning missions records, casting his gaze over them and easily categorising them by their jikusaki without thinking.

It took a little more work than that to find what his kohai had been up to most recently . . . but not too much, because he knew what they often sent Tenzou to do. It was on the third report he checked that he found Tenzou’s perfectly neat, slightly square writing.

Kakashi contemplated for a moment, skimmed over the report - his body tingled with fretful energy and he frowned - then tucked it neatly away inside his armour, out of sight, and slipped out of the records room. No one would be surprised to see Kakashi there, though truly he shouldn’t be, having been pulled from ANBU completely to oversee his team of genin - but few saw him at all, as he flitted through the corridors and tucked himself out of sight, high in the building, in a space that would admit few mers.

Likely most would not have thought Kakashi would fit into it either, squashing himself with his tail curved up before him and around to rest behind his head, but Kakashi had always bent more easily - and further - than most sharks. Even of his own kind.

Kakashi read over the flat, detailed, precise words of Tenzou’s report, fingers trailing over the characters. His stomach knotted and his heart ached. Tenzou had been sent alone, and he had done well - had returned home exhausted and wounded but whole and successful - but he had been alone.

Tenzou was so often alone, now, on his missions. Kakashi could count on one hand the number of times he had been sent out with a team in the last cycle of currents. It made Kakashi ache with worry, and much as he didn’t miss the weight of ANBU missions. . .

The simplicity behind the mask was sometimes dearly missed, and even more he wished, desperately, that he could be there for his kohai still. That he could argue or shift assignments, either by dint of being the taichou in command or simply . . . adjusting things, without asking and without waiting for confirmation.

At times Kakashi did that now, though it took a little more work. Those ostensibly in command of ANBU missions were at times those most lacking the information to appropriately assign teams - or solo ANBU - to those tasks. Kakashi felt not a sliver of regret for fixing those mistakes.

Kakashi rolled the report up once more. He would need to return it to the records room before anyone noticed it was missing, and probably remove himself from the building. If he couldn’t engineer a way to run into his kohai once again whilst he was here, or perhaps . . . perhaps it might be better - as Tenzou might be distressed to see him here - to do so elsewhere.

Report returned to its proper place, Kakashi checked the rosters and scowled; Tenzou was already out again, alone again. Kakashi slipped out via another way than the one he had used to come in, and though he’d intended to do some shopping and return home, he headed back out to the training fields alone instead.

Kakashi needed to vent some of the tension coiled inside him after his checking in on Tenzou, at the least. And he told himself it would soothe the twisted, sickening ache in the pit of his belly when he let off some of his frustrated aggression in training.

His heart ached as he went through the beginnings of a warm-up kata, and Kakashi contemplated looking up Gai instead. Gai was always good for a consuming distraction.

And Gai understood him all too well, might very well guess that he was distressed but . . . Gai knew him all too well. Gai would not ask.

Kakashi snarled and reduced a boulder to rubble, watching the shards filter down to settle among the plants on the seabed. He lashed his tail and immediately began another kata, body thrumming with frustrated emotion he couldn’t- He couldn’t-

Kakashi bared his teeth and abandoned the field, turning tail and going to seek out Gai.

Tenzou pressed a hand to his side, moving stiffly. It was . . . easier, now, within the kelp forest. The plants offered their energy with barely a brush of his own chakra, and it kept him going, at least.

. . .easier . . . was relative.

Tenzou was moving, but only just. He’d made it further than he’d expected, though. He was . . . close. He had achieved his objective and gotten out clean, he had made it back to Konoha, he had even almost- almost made it to Kakashi. To home.

He pulled himself along further, bones grating in his chest. His gills flapped helplessly. He had staunched the bleeding leagues back, but he was weakening fast. Tenzou suspected he was still bleeding on the inside. He could feel the heat and the knotted pressure inside him, growing, hard and painful.

He wasn’t going to make it any closer, Tenzou realised as his vision pulsed with grey-black, and he momentarily lost even the sensation of the water moving around him. It returned in a rush that Tenzou belatedly identified as actually being the rush of new currents moving around him.



Tenzou groaned, squinting and making out the brilliant orange and faint pink of two of Kakashi’s students. A dark shadow passed over them and he heard them start to scream. His vision faded further.

Kakashi-sensei! Come help! There’s a ninja! He’s one of ours he’s got our leaf! Who is he?”

Their voices mingled into a cacophony, he had no sense which words began to which of the youngsters, and he quickly lost the sense of the words at all.

At least, Tenzou thought as he felt himself sinking further towards the seabed - even the kelp couldn’t catch him now - he’d made it almost back to Kakashi-senpai. He might even see Kakashi again. He would like that, he thought as he felt slender, slick leaves slip through his fingers and tangle with the trailing, leafy fronds of his fins. He would like it if he could see Kakashi, once more, before. . .

Tenzou thought perhaps he might even not mind so much. He’d been so very. . . He was a good ninja, a good ANBU, he’d followed his senpai’s philosophy. If he fell now. . .

“Oh fuck. Tenzou.

It wouldn’t be so bad if he fell now, Tenzou thought, then jerked a little as bony hands settled on his sides, catching him up before he could sink deeper. “Kakashi-senpai.” he managed, thin and gurgling. Kakashi’s tail brushed his own, smooth and strong, and Tenzou twitched again, then choked as pain lashed through him.


“It’s all right.” Kakashi said, and Tenzou, at least, could hear the tension in his tone. He wondered if the genin could hear it. He was lying, of course, but Tenzou felt a surge of fondness for him for it. He said it again, softer, and Tenzou whimpered at the barely-there brush of tough material against his brow, and then soft hair tickling his face. “You’re safe, my precious kohai.”

Tenzou’s fingers twitched, nerveless and weak, as he struggled to clasp hold of Kakashi. His tail ached as he moved, and his upper body throbbed with pain, stiff and heavy - not a good sign, but he’d known that - but he did a little better as he curled his tail against Kakashi’s own, just barely hooking past one of his pelvic fins.

“I’ve got you, Tenzou.” Kakashi said, or perhaps Tenzou just imagined it, as he felt Kakashi’s tail begin to move in a steady beat, the water and the kelp sliding over them. It was the only thing he felt for long moments, comforting and steady, and then it, too, was gone.

Kakashi fiddled with the edges of his book, then put it down again, circling his den restlessly. He never quite strayed away from where Tenzou lay on the soft sand flooring his den, though; his precious kohai was . . . stable, but. . .

Kakashi settled down at Tenzou’s side, his underbelly nestling into the sand. It was reassuring, such as it could be, feeling Tenzou’s heart beating and the flicker of the energy in his body. Kakashi’s lateral lines tingled a bit with it, he’d been focusing so tightly on Tenzou ever since he’d been allowed to take him from the ANBU treatment caves. He smoothed a hand over Tenzou’s belly, from amongst the fronds of his pretty, plantlike fins to the flat planes of his muscular upper body, stopping just shy of his chest. He’d been battered and bleeding inside, here; organs ruptured and beginning to die.


He might be stable now, but Kakashi had almost lost him.

“Oh, Tenzou. . .” Kakashi dipped his head, closing his eye, and his gills flapped hard for a moment. “My precious kohai,” he shuddered, gasping, “I. . .” Kakashi’s tail twitched, and he was careful not to press any nearer to Tenzou, to risk hurting him. “I almost lost you, Tenzou, please-”


Kakashi jerked, eye snapping open and tail stiff. Tenzou’s own twitched. “Tenzou!

Tenzou smiled weakly, his eyes a little wide and confused. “Hello, Kakashi-senpai.”

His voice was thin and a bit warbly, catching in his throat with a burble, but he was speaking, he was-

“Oh thank Ryuujin-sama.” Kakashi said in a thoughtless rush, fingers smoothing over Tenzou’s ribs in a hurried stroke, arm winding around his waist as Kakashi let himself settle, very carefully, snug against his kohai’s side. “Tenzou, you’re-”

“I’m glad.” Tenzou said, a faint smile softening his wide mouth. Kakashi shuddered, gills flapping open wide as he drew in a deep gulp. He found a shaky smile for Tenzou in return. “I hoped I would get to see you again.”

“I’ve missed you, too.” Kakashi spilled, not quite able to catch the words back, then choked, staring at Tenzou as he kept speaking. “What?” he half-rasped.

“It was all I wanted,” Tenzou repeated peacefully, “to see you once more. . . If I was going to die, I didn’t want to. . . I just wanted to see you again, Kakashi-senpai. . . My most precious person.”

Tenzou.” Kakashi protested thinly.

“It’s all right, senpai!” Tenzou assured him. “I wouldn’t- I don’t mind. It would have been all right, I think. To die for my village, to not be-” he broke off. “I only wanted to see you again. My Kakashi-senpai.”

“Tenzou!” Kakashi’s voice was stronger this time, and he pushed himself up just enough to move over Tenzou, catching his gaze.

“I missed you. . . I-” Tenzou ducked his chin. “I’m sorry, senpai.”

“Don’t- I-” Kakashi’s words hitched and his chest ached. “I’ve been watching over you, when I can. How I can.” he admitted painfully. “If you had- If I had lost you, because I wasn’t there with you, because of a mission, if- It already felt like I’d lost you but Tenzou if you died. . .” Kakashi’s throat tightened painfully as he remembered his pups screaming for him, remembered finding Tenzou limp and sinking, his own heart seizing as he lunged, catching hold of Tenzou. . .

If Tenzou had died there in his arms instead of only sinking into unconsciousness. . .

Kakashi keened, unable to keep the sound back. He sank down against Tenzou, tail curving around Tenzou’s as he slipped his arms behind Tenzou’s shoulders, trying not to cling too fiercely but unable to let go.

“. . .Kakashi-senpai?” Tenzou said faintly, but his tail was winding around Kakashi’s, clingy and needy. Kakashi shivered, tail tensing and curving down a little more, pressing Tenzou between himself and the sand, as Tenzou’s long fins tickled over his skin. “Kakashi?” he said again, fingers twitching as they slid up over Kakashi’s bicep to curl around his shoulder.

“You’re precious to me too.” Kakashi said, feeling the words from wretchedly deep in his chest.

“Kakashi?” Tenzou’s eyes were wide and his gaze almost hurt.

Kakashi bowed his head, closing his eye and hiding his face away beside Tenzou’s cheek. He thought of having Tenzou so close, of what it would have been like to-

“I don’t- I can’t regret being pulled from ANBU,” Kakashi said softly, thick and rough; though he did sometimes wish he’d been pulled for anything but wrangling a team of wild pups he had no idea how to teach, “the only thing that I regret is that it took me away from you.” He flicked his tail, pulling Tenzou up off the sand, safely clasped in Kakashi’s embrace with their tails wound closely together, and slid his arms lower around Tenzou’s back. “I need you, Tenzou.”

“Kakashi!” Tenzou startled in his embrace.

Kakashi nuzzled his jaw. “Stay with me.” he begged.

Tenzou squirmed a little, and Kakashi almost felt a frisson of alarm, but Tenzou’s tail only curled tighter around his, one of Tenzou’s arms clamping around his waist. “I. . . Kakashi?” he asked as they settled on the sand together. “Kakashi, can. . . Erm.”

Kakashi lifted his head, only feeling a little unsteady. Tenzou’s hand slid shakily away from his shoulder, and he reached up to touch Kakashi’s face. Kakashi tilted his head, not quite nudging into the not quite caress.

“Kakashi?” Tenzou said softly, and he opened his eye, humming a response. “Can I. . .”

“What is it?” Kakashi asked, searching Tenzou’s face. He froze as Tenzou’s caress slid over his mouth. He swallowed hard and Tenzou made a soft whining noise, squirming deeper in the sand beneath them. His fins flared and folded forwards, but he could hardly hide from Kakashi, not when they were so close, wound together and- “Anything, Tenzou.” he said, throat tight. Meaning it.

Tenzou’s eyes darted back up to his own, wide and shocked. Kakashi nodded slightly, and Tenzou shifted beneath him, then lifted his head and brushed a feathery kiss to Kakashi’s lips. He felt the caress of the current left behind as Tenzou ducked away again almost more than the brush of skin on skin.

“Tenzou.” Kakashi said, stroking his cheek.

“I just-” Tenzou peeked up at him cautiously. “Just once, maybe, but I- You’re just-”

“Tenzou,” Kakashi interrupted him, twisting their bodies closer still and letting his own back settle onto the sand, Tenzou held snug against him, “anything you want, precious.”

Tenzou twitched, delicately leaf-edged gills fluttering. “. . .truly?” he asked, aching hope and hurt in his voice that made Kakashi ache in turn.

Kakashi tipped his head, their noses just brushing. “Please.” he encouraged gently, and Tenzou took a deep draught and then-

Kakashi clicked softly, not quite surprised but deeply pleased by the gentle, firm contact as Tenzou kissed him again. Kakashi looped an arm behind his neck, keeping him down and close, tail wriggling, nudging up against him in turn.

Tenzou gave a soft, whistling trill, his own tail all but trembling even as he clung to Kakashi ever tighter. Kakashi’s tail was just shy of aching from the almost desperate hold Tenzou had on him, but he wouldn’t have tried to loosen it for anything.

He smoothed a hand over Tenzou’s tail, fingertips teasing through the leafy fronds of his fins. Tenzou trilled again, softer for being muffled against Kakashi’s mouth, the sound tickling the back of his throat and the inside of his gills, almost making him laugh. Kakashi drew his teeth gently over Tenzou’s lip, free hand pushing into his hair, stretching their bodies together with only just enough care not to strain Tenzou’s recently-healed body.

“Anything, Kakashi?” Tenzou asked softly, gold-lit brown eyes warm and happy.

Kakashi smiled and stroked his hair, heart eased to have Tenzou wound up with him, safe in his embrace, in his den . . . sharing the sweetness of long kisses and twining tails. “Anything, precious.” He cuddled Tenzou closer and nosed along his jaw.


Omake in Three Parts:


Naruto yelped as he fought to free his frilly, streaming fins from Sakura’s grip. “Sorry, sorry!” he said hurriedly, caudal fin waving back and forth hard. “I won’t do it again!”

Sakura clicked rapidly, tail flicking. She released his fins - she’d had a tight grip, but as much as it had been alarming, she hadn’t hurt him at all; Naruto guessed now that he might have actually hurt her more, pulling her hair - and patted his side just beneath one.

“See that you don’t!” Sakura huffed, then absently tugged at a few of the fine, trailing ribbons leading off his fin, smoothing them out unnecessarily. Naruto fought not to snuggle into her at the touch, fins fluttering. Sakura smiled, bright and a little alarming from this close - so close the vicious sharp tips of her teeth were visible.

Naruto jerked. “Whoa! Look!” he cried, and Sakura twisted, alarm drawing taut every line of her tail as Naruto’s spines flared outwards. It made it clear what she was, as her usual softer poses often disguised - like this, she looked akin to their sensei, angled fins ready to cut through the water, sleek body built for hunting.

The kelp forest rippled again, and then-

“Oh! It’s that creepy-eyed mer!” Naruto said, fins waving, halfway towards relaxing. It was someone familiar, and while he looked strangely like part of the kelp forest come to life - Naruto hadn’t been sure, before, if he was really a mer or some kind of jutsu or a monster - he was. . . A friend, Naruto thought.

He thought of Kakashi-sensei catching the strange mer with gentle hands, then not only catching him but cradling him close, crooning to him, calling him by soft names when he went limp.

The mer smiled at them, broad and a little strange, and waved one hand, his strange fins waving like the kelp behind him.

“Tenzou!” Kakashi-sensei greeted, and Sakura relaxed a little more as Kakashi-sensei darted past them and met the other mer with hands outstretched, beckoning him in.



Tail thrashing impatiently - he was better than this, they could be moving faster than this, why did their lazy, irritating sensei insist on going slow for the others, if they couldn’t keep up they weren’t worth it - Sasuke made another round of the field and settled into his kata. He forced himself to slow, doing it properly, and shut out the memory of his mother’s hands guiding him as he learned, her long, strong tail shadowing his entire body.

Sasuke’s gills trembled and he drew in a deep gulp, throat locking and gills twitching briefly before he managed it again. He stretched out his arms, arched his back, and continued. He glared over to where that strange mer who had come back half dead weeks ago and interrupted their training was working through something with Naruto.

Naruto flitted about the jounin, stupid too-flashy fins confusing his sloppy movements even more.

Why had Kakashi-sensei asked him to work with Naruto? Naruto was- was the dead last of their class who’d barely graduated to genin even with exceptional circumstances. He didn’t deserve the special attention any more than-

Sasuke almost glared the other way, but quickly stopped himself. He didn’t need to look to see Kakashi-sensei working with Sakura, whatever it was he’d spent most of the past three days doing with her, as though it would matter.

“How are you doing, Sasuke-kun?” Kakashi-sensei asked, and Sasuke tensed and didn’t look at him even as he put a hand on Sasuke’s shoulder. “Loosen up, you’ll hurt yourself that way.” His tail tapped Sasuke’s gently.

“I know how to do it.” Sasuke snapped, yanking away from his sensei and stretching a little further, a little faster. He ignored the ache from yesterday, and the day before. He just needed to push through it.



Sakura groaned as she stretched out once more, twisting every way she could - she took pride in how far and how well she could; most sharks were not known for their capabilities this way, but she’d worked hard - and then pushed through the kelp to leave the practise area. She knew some of their agemates found the kelp forests like this one creepy, or hated swimming through their tall, thick growth, but she loved it.

The leaves brushed her sleek sides, and Sakura timed the strokes of her tail to the currents that made the kelp sway. It was fun, and-

Well, Sakura had been . . . a little surprised, the second day Kakashi-sensei had drawn her aside to work on endurance exercises alone - she had worked as hard as she could, anxious to prove she could do as well as he thought, to prove she appreciated his time training her one on one - to be told it was also good practise. Sakura had enjoyed it a little more since then, even.

She giggled to herself as she twisted and looped through the kelp, timing her strokes properly, and then flailed a little as she reached the edge, ducking promptly back amongst the leaves. She peeked around them.

Naruto was just disappearing around a tumbled fall of rock, his bright tail easy to pick out, as it always was. Sasuke had already sped off on his own, the moment they were done in the sheltered area that hosted their training.

Sakura had hardly needed to guess to see how unhappy he was that Kakashi-sensei was working with her most of the day, though he had checked on the boys and their own training often, and Tenzou-sensei had worked with them too. It was. . . Sakura liked working hard, liked having Kakashi-sensei’s focus on making her better at the things she could do, and she resented Sasuke’s assumption she couldn’t be better. She resented it a little more with every bit of praise from Kakashi-sensei and every new exercise she mastered.

The boys were gone, though, and Sakura remained in the kelp, and there, where it thinned out a few dozen lengths away, were Kakashi-sensei and Tenzou-sensei. He had told them he wasn’t a sensei and they did not need to call him that, but he was teaching them - especially Naruto, with mingled patience and confusion that made Sakura giggle to see - and he deserved the title.

He wasn’t a teacher, it was obvious for all his efforts with them, and Sakura had quickly gathered he was doing this for Kakashi-sensei.

Sakura ducked a little more behind the kelp fronds, stifling her giggles. Kakashi-sensei and Tenzou sensei were twined together in the verges of the furthest arm of the kelp forest themselves, tails wound around one another. Kakashi-sensei was toying, one-handed, with one of Tenzou’s long, leafy fins, and he was smiling more softly than he ever did at them.

Sakura thought they were kind of cute. For her ridiculous old sensei. Sakura darted out of the kelp to head home, and startled as Kakashi-sensei flicked his fingers in a lazy wave - she hadn’t realised they’d seen her.

Sakura waved, heartbeat speeding a little with embarrassment, and quickened her pace, leaving her sensei behind.