Someone pointed out on one of my Mer AU posts that sharks have two dicks and next thing I knew the horny activated and my hand slipped
Anyways have 2k of GrisVolo Mer AU smut (Akari gets to watch)
Biology Lesson
Pairing: Gris/Volo (with hints of Gris/Akari) Rating: Explicit Words: 2,328
CW for explicit sex, inhuman biology, voyeurism, light breeding kink, mentions of gender identity/dysphoria
“So, um… how does it work, exactly?”
Both Volo and Gris glanced up at the question. Akari flushed as she felt their attention on her, two sets of eyes glowing out from the darkness. “How does what work?”
Akari swallowed. It took a moment to find the words, still distracted by the scene in front of her. Gris lying sprawled out across the large rocky ledge in their grotto, with Volo lying atop them, tails curled around each other as Gris’s tendrils kept him held loosely to their chest…
She blushed again. She knew her hosts were lovers – or future consorts, as Volo had proudly put it – but seeing them be so casually intimate was still an adjustment. “Um,” she said, still hesitating, “I mean… you two. Being together. How does that… work?”
Gris arched an eyebrow. Volo spoke up before they could. “Oh it’s not that difficult, actually,” he said. “Yes, there’s a pretty sizable gap in our stations, but Aure smoothed over most of the court’s objections when they gave their blessing. Plus there’s precedent for merfolk royalty choosing their own consorts regardless of rank. In fact, during the reign of–”
“Volo,” Gris said, looking at him with amusement, “I don’t think that’s what she was asking.”
Akari blushed deeper. Volo glanced between her and Gris for a moment, blinking, before it seemed to dawn on him. “Oh,” he said. “You mean physically?”
She nodded, face still red. “...Yeah.”
They were both looking at her again, eyebrows raised. Akari coughed and looked away. “I mean,” she said, making a few feeble gestures with her hands, “I was just… wondering how the mechanics of that works? With you both having tails? And completely different tails too. But then again, I’m not really sure how any of this works…”
She glanced down at herself, taking in her own transformed lower half. It was still… jarring, seeing a tail where her legs should have been. It felt so alien to her, unfamiliar muscles beneath smooth blue scales, and dark armored spines unlike anything she’d ever seen before…
Gris had apologized for it when she woke up. Confessed that they’d cast the transformation spell in a panic, not knowing how else to save her. She didn’t hold it against them. She would have drowned in that shipwreck if it hadn’t been for their magic.
She coughed again. It came out awkwardly, half of the air huffing through her new gills instead of out her mouth. “Never mind,” she mumbled. “It’s probably rude to ask that kinda thing.”
“Perhaps.” Gris pushed themself upright, tendrils swaying. “But I’ll overlook a little impropriety, coming from you.”
The currents around her shifted. She glanced up to see one of Gris’s tendrils reaching out for her, their claw gently brushing across her cheek. When they smiled, it made her heart skip a beat. “You were wondering how Volo and I mate?”
She blushed, but nodded. Gris chuckled and turned back to look at Volo. “Well then,” they murmured, “I wouldn’t object to a demonstration.”
They slid a hand down Volo’s front, letting it rest on the smooth underside of his tail. Volo let out a faint, shuddery sound through his gills. “Gris…”
“May I show her?”
Volo nodded eagerly. Gris glanced back at Akari, one eyebrow arched in question. She swallowed hard when she realized what they were asking. “Yes please,” she said hoarsely.
She hoped it didn’t sound as eager as it felt. Gris chuckled again, rubbing two fingers along a spot on Volo’s tail. Volo shuddered, fins twitching, before melting against their chest. Beneath Gris’s fingers, Akari saw a faint, fluttering line on Volo’s tail that she hadn’t noticed before.
Gris hummed, stroking their fingers along that line. It parted open like a seam, and they dipped one finger inside, teasing out the tip of something slender and pointed. “Eager today,” Gris murmured.
“Apparently I don’t mind having an audience,” Volo replied, before trailing off into a groan as Gris’s fingers dipped deeper into his slit. “Gris…”
“Come now, we’re going to do this properly. That means both of them.”
Volo shuddered and nodded. Akari watched in fascination as they coaxed not one but two shapes from Volo’s slit, a pair of cocks easing their way out. “He has two?” she blurted.
Volo managed a grin in her direction. “Perks of being a shark merman.”
“To say nothing of those teeth you are so proud of.” Gris pressed their other hand to Volo’s mouth before he could respond, prying it open to look over his rows of sharp teeth. “It took quite a bit of effort to teach you how to use that mouth without biting all the time.”
Volo made a noise like he was trying to give a witty retort, but it was quickly muffled by Gris pressing two fingers on his tongue. They smirked as he relaxed his mouth around them, tongue lazily swirling around their fingers. “Well-trained,” they murmured, before pulling their hand back and focusing on his cocks once again.
It took only a few more teasing motions before they’d coaxed Volo’s cocks out all the way. Akari stared at both in fascination. They were so different from anything she’d seen on a human, longer and more tapered, and bright-red to match the patterning along Volo’s chest. She found herself wondering if they worked differently to a human cock as well. Not to mention how they would feel…
Gris gave each cock a single, languid stroke, then moved their hand beneath both, fingers sliding past them and back into Volo’s slit. “Volo is capable of both giving and receiving,” they said, as Volo moaned and shuddered around them. “Normally I have him receive me. But I can allow him to give this time, if that is what you would prefer to see.”
They looked at Akari expectantly. She startled at the question, staring back in surprise. They… were letting her choose? Just letting her watch as they demonstrated sex with Volo was generous enough. If anything she’d figured they were just using it an excuse to fuck Volo, but…
They continued to watch her, patient, indulgent. Her cheeks flushed. “...Whatever you’re most comfortable with,” she mumbled. “I’m not picky.”
“I see.” Gris chuckled, turning back to Volo. “Then you will be receiving again today.”
“No complaints there,” Volo got out, before Gris pushed their fingers deeper and he trailed off into a moan. “A-ah, Gris…”
He continued to whimper as Gris worked him open, cocks twitching with each brush of their hand. At last Gris was satisfied and pulled back to rub two fingers along their own front. A seam shivered open beneath their touch, and their fingers slipped inside it, exhaling low groans as they coaxed out their own cock–
No. Cocks.
“You too?” Akari said, staring at both of the dark, sinuous shapes that snaked out. “Seriously, how many merfolk have two of those things?”
“Not many.” Gris gave her a smirk. “Volo and I are well-matched in that regard.”
She could still only stare. Gris’s cocks were different from Volo’s, pitch-black and curving, and positioned one on top of the other instead of side by side like Volo’s were. They also seemed to have a mind of their own, swaying out towards Volo the same way Gris’s tendrils did. Gods, she wondered how those would feel inside her…
She bit her lip to keep in what would have been a very embarrassing sound. Gris didn’t seem to notice, too busy lining themself up with Volo. “Now then,” they murmured, tendrils coming out to wrap around him. “Shall we?”
Volo let out an eager whine, tail bucking against them. Gris looked to Akari next, and she swallowed hard. “Um, yeah. Go ahead.”
They smiled. “Watch closely,” they said, and pushed in.
Volo’s groan as their cock slid inside him made her shiver. Gris sank deep without issue, exhaling a low noise of their own. Only their lower cock had actually pushed into his slit, Akari noticed. The upper one had instead pushed between the gap in Volo’s two cocks. They provided just enough opening for it to slide back and forth, rubbing sensually against both.
Oh, Akari thought, feeling dizzy from the sight. Oh, they really are well-matched.
Gris didn’t allow her to dwell on that thought before they snapped their hips forward. Volo choked out a keening noise, hands flying up to grip their shoulders. “Yes,” he gasped, tail fins kicking desperately. “Yes, yes…”
Gris thrust again. He moaned, arching against them. Akari watched as the two instantly fell into rhythm, bodies rocking against each other, fins swaying back and forth to keep them upright. Volo clung to Gris’s shoulders as their tendrils wrapped around him, keeping him pressed flushed to their chest as he was fucked.
Akari’s own tail flicked, squirming as she watched them. Volo’s moans were echoing through the entire grotto, as were Gris’s own noises, breathy murmurs and exhales and the occasional groan when he shuddered around them. When they spoke, their voice was a sultry rasp. “You feel warm.”
“Mmmnn, hah…?”
“Yes, warmer than usual….” Gris’s hands wrapped around Volo’s hips, their pupils dilated larger than Akari had ever seen them. “Are you in season?”
“I– nnnh…!” Volo couldn’t speak at first, still clinging to them and whimpering. “N-no, but I think I’m c-close to it…”
“Then it seems we best be cautious these next few weeks.” Gris leaned in closer, voice dropping. “...Unless you think you’re ready to bear my children.”
Volo let out a sudden, needy whine. Gris growled in response, leaning in to press their mouth to the crook of Volo’s neck. “Oh? Do you want that?”
“Gris–”
“Perhaps I should give it to you, then.” Gris’s tendrils tightened around him. “Steal you away to my lair for the entirety of your season. Bind you to my nest and mate you until you have no choice but to carry. You would look good like that, wouldn’t you, so heavy with my eggs…”
They punctuated it with a thrust so deep it made Volo cry out. His nails scrabbled at their shoulders like he was trying to steady himself, before giving up, choking on a broken, desperate noise. “Close,” he begged. “Close, close, please…”
Gris drove in one last time. Volo’s entire body seized up as he climaxed, crying out their name. His cocks disappeared beneath a mist of pearl-white seed. Gris growled and rutted their cock through it, before spilling a cloud of something much thicker, and black like ink.
Volo's hips twitched and rocked through his climax, before he finally slumped against them, groaning. Gris exhaled a heady noise and loosened their tendrils. “Good?” they murmured.
“Mmm….” Volo curled closer to them, nuzzling his head under their chin. “Always.”
Gris smiled and kissed the top of his head. They kept Volo pressed close to them as they turned back to look at Akari. “And there you have it,” they said, as casually as if nothing happened. “I hope that was informative enough for you?”
Akari stared. She was sure her cheeks had to be flaming red, given how warm her whole body felt. For a moment she wasn’t able to say anything. All she could do was take in both of them, still thinking about everything she had seen and heard…
“What was that about eggs?” she blurted.
Volo let out a weak snort. “That was dirty talk. We’re not demonstrating that.”
“Yes, we’re a ways off from being ready for children.” Gris chuckled and stroked a hand through Volo’s hair. “But it does not keep me from teasing him about it whenever he’s near his season.”
“Oh.” Akari tilted her head to the side, curiosity once again outweighing her embarrassment. “But… he is capable of it?”
“Of course,” Gris said. “As am I. Most merfolk are both male and female.”
“Yes, we don’t exactly do the whole gender thing the way you humans do.”
Akari blinked. “But, you called yourself a merman–”
“Personal preference.”
“He’s a bit eccentric for it,” Gris teased, poking Volo in the cheek. “Most of us don’t tend to choose one sex over the other. But Volo spent so much time studying humans that a few things rubbed off on him.”
“It just feels better,” Volo insisted. “I know the humans get ridiculous over these things, but I like drawing that kind of distinction for myself. Plus I just prefer the imagery that comes from being a man. You know, all strong and dashing, with a touch of roguish flair…”
Akari listened, biting her lip. She… understood where he was coming from. Being a princess wasn’t necessarily bad, and she didn’t hate being female. Especially not when her father had made it clear that she was allowed to do all the same things a man could, court advisors be damned. But everyone still whispered about what a princess was supposed to be like, and whenever she didn’t fit that mold she found herself wishing she could call herself a prince instead…
“I’m a bit jealous,” she mumbled. She wrapped her arms around herself, sighing. “That you guys get to choose like that. I wish I had both sometimes…”
She shot a wistful look down at her tail. Gris and Volo paused, exchanging a look of their own. “...Akari,” Gris said at last. “You are aware that spell was a full transformation, right?”
She blinked. “Uh, yeah…?”
“Which means,” Gris said, drifting closer to her, “that your sex should have been altered to match a merfolk’s as well. In other words, assuming that my spell went off properly…”
They pointed at her tail for emphasis. “Then you do have both.”
She stared. Gris stared right back, pointing at her tail with one eyebrow raised. She looked down at her tail, then back at them, needing a moment before their words properly sank in. Once they did, her mouth fell open.
“Wait, I do?!”
