"Is it in yet?" The orca shouted to the smaller cetacean near her folds. Mara's tone was annoyed; the dolphin just hadn't been a good choice of a mate.
"Of course it's in!" Ven roared back, panting. "If you weren't such a huge sea cow with a loose pussy, I'd–"
"Oh, fuck off, you overcompensating little shit. If your dick was as big as your talk, maybe you could please a lady like me with that pathetic flailing that you call 'mating'."
"Fuck you."
"I wish someone would." Mara retorted.
Ven groaned and swam away from her reach, letting his erected pink spire slip out from her vaginal slit.
"What now?" The orca asked. "Don't tell me you came from -that-..."
"Very funny. I'm just trying a different position."
A different position...? The dolphin touched his body to hers again, after turning around to point his head towards her tail. Seriously, Mara thought, this guy was just a waste of her time, and the killer whale now wanted to get rid of him and look for a real male – one as big as her, at the very least. However, pushing Ven away would've been a tiresome effort... but she had another idea brewing.
She brought her black-and-white tail, pressing it to his own flukes. But instead of sliding Ven's fin away from her belly, Mara pulled him towards her hind end, and his long snout got snagged into her labia.
"Whoa!" The surprised dolphin exclaimed as the orca's sex grabbed onto his face and didn't let go. "What's going on?!"
"How's this for a different position, eh?" Mara teased him, her muscles pulling him deeper than his cock had been able to reach. Ven's whole head had been swallowed with relative ease, filling up her whole canal as the dolphin's nose poked her cervix. "Y-Yeah... So much better."
"What the fuck are you doing?! You stupid sea cow!" The gray cetacean tried to squirm, but her sex's hold was too tight around him. He could only stare into the entrance of her womb while Mara's tail fins thrashed her own body around in the water, mimicking thrusting. "Are you riding my head?"
"Just face it, Ven. You're a better toy than a mate... Mf!" His dorsal fin was pushing against the entrance of her vent, while the upper part of his slick body squished a mixture of seawater and her own juices. Being underwater, she'd struggle to manage her breath even as her arousal built up. "N-Now be quiet and let me handle it."
Despite his raging erection, the dolphin was too prideful to let Mara simply use him. And with her vagina's recess in plain sight, he'd already formulated a plan to get the upper flipper. He flicked his own tail, torpedoing his whole body until his snout was driving against her sphincter – only to learn firsthand just how lax it was instead.
"A-Ah! My womb...!" Ven was stretching her, and she could feel every little prod and shuffle of his nose further in her sensitive organ. "You little fucker– hmng!"
"Ah, so now I'm fucking you, huh? How's that for a mate?"
Mara was loving it, plain as day. But she wouldn't admit it, to not discourage her adversary from storming into her most intimate parts. His flippers glided along her birth canal to drag his dorsal fin inside, while his tapered dick leaked precum that mixed into the salt water, much like the vaginal lubricants escaping Mara's folds.
Ven was more concerned about trying to be a pain in her butt and pussy. "Huf... How loose are you? No wonder you're so cranky, if you need a whole 'phin jammed into you to moan so much."
"Listen here, you little shit–hmmmnnggghhh-ooh...!"
His whole head had pushed into her uterus. With his cock inside of her again, smooshed between his body and her G-spot, Ven slowed down the swimming motion of his tail, humping against the wall instead of propelling himself deeper.
Yet, Mara's vagina still slowly sucked him in through lustful clenches, depositing more of the blubbery prey into his only possible destination. She didn't want that annoying twat in hers – or at least, Mara had to tell herself that much. But it was hard to hide how good it felt when Ven penetrated her so deeply and thoroughly.
"Haah...! Finally learned how to treat a lady, fishy toy–? HmmNG...!"
Ven scoffed and panted from inside, continuing his thrusts. "A lady? Huff... You're an insatiable sea cow, is what you are...! Mph!"
That snarky little prick...! Mara clenched down harder on him, hoping to suck him into her womb and deny him an early release. The effect was the opposite – with her cervix stretching to accommodate his flippers, and the walls of her organs scrunching on him, Ven whistled in his intense orgasm, each spurt splattering dolphin spunk into a deeper part of her folds thanks to Mara's rhythmic swallows. He was too distracted to realize just how deep the orca was willing to take him, his tail fins having to curl into her tunnel as they, too, slipped past her labia.
After Ven, it was her turn to reach her peak. It felt like her whole body contracted, the obvious source being her vagina still consuming the smaller cetacean fully hidden inside of her. She let out a deep wail of ecstasy, a sound that would likely propagate far underwater. Riding through the high, she looked down at her sex, shut again after gushing globs of a white fluid being broken down in the ambient solvent. Ven's bulge still traveled deeper into her, more and more of her small plaything settling past her cervix.
Ven's long and slender body had to curl quite a bit in this fleshy prison, swirling his head with an U-turn at the back wall to fit in what little space he could find. His tail slipped in and unfurled, the flexible fins flapping onto his face as he managed to finally settle in the orca's womb. Ven was contorted in a circle, barely able to move as he panted and breathed down the damp air.
"Fuck...me..." Mara said. She rushed to the surface to catch her breath, then submerged again. "That wasn't...half bad..."
"Half bad?! You ate me with your coochie! What's fucking wrong with you?"
"Oh, shut up, you little shit... I could feel you cumming in there!"
With their euphoria fading, the antagonistic couple was back at their bickering Manners with each other.
"W-Well, so did you! I told you I could do it!" Ven yelled back at her walls, trying to squirm to find the entrance. "Now let me outta here!"
"Nuh-uh. You promised me 'my best orgasm ever', and that wasn't it. You're staying in there until I get what you promised."
His face flushed with red, and his dick got fully engorged. There was no way to do much in his situation, but what really flustered the dolphin was when he realized that he couldn't hump any surface of her womb with his protesting member, or bring any fins close enough to stroke himself. He'd just have to wait out, for who knows how long, inside of... -her-.
"S-Stupid sea cow..." Ven grumbled quietly.
"Silly fishy toy..."
Mara turned around and swam away back to her pod, hoping to find a better mate for round two. A big one, this time – she wouldn't make that mistake twice.