I got horny

The black dragon growls deep and long as he cums, pleased to finally release the load he'd been saving for months now. She shudders and shakes himself, pulling out and splattering the dragoness with one last rope of seed. The cave begins to smell of dragon spunk. He grunts as his monstrous cock twitches and throbs in the cold air, still trying to pump a load already spent. He gathers himself and ignores the aftershocks of pleasure, he has work to do.

He steps around the bound and splayed female, eying her slit as it oozes his seed; the scales around it still tinted pink with her autumn heat. She is without a doubt fertilized. He ungags her, but she says nothing, still quivering with her back against the floor as she bathes in the afterglow. That was fine with him. He moves behind her, placing a paw on one of the many runes he had carved in a circle around this spot.

"Oohhh... That was amazing. I can't believe I hadn't tried that before," she says huskily, her voice still thick with lust. "You can untie me now. I want to try it with you next."

"Not yet" he replies, concentrating on his spell.

"Why not?" She asks, playfully.

"Because I am impatient."

"What do you- Aahhh!" She cries out as the runes around her suddenly blaze with blue light.

"What is this!?" She demands, her voice shrill and commanding. She grunts as her abdomen tenses uncontrollably, squeezing with all her might.

"What was that? What have you done to-ooOOoohh!" She groans as her belly lets out a loud rumble, then swells forth, turning her slim figure into a paunch in mere seconds; and the growth doesn't stop. He roars of displeasure become whimpers and shrieks of fear.

"What's happening to me?!" She cries as her middle gurgles, surging larger while she tugs uselessly at her bonds. She pants as the scales across her face tinge red.

"I am impatient. I do not wish to wait a year for you to birth." The onyx dragon replies.

"W-what!? Y-you mean I'm..." She stares down at her midsection as it burgeons with eggs. Only now can she feel them in there, shifting around as more form and push together. It gurgles again and begins swelling more quickly, rapidly approaching full term... And then passing it. She moans and lays her head back, her confused body misfiring and sending spikes of pleasure through her body at random. "There are so many... Oohhhh how much bigger am I going to get?"

"I don't know." He admits. "I used virility spells on myself, and I have been saving my load for months."

She arches her back, the scales across her abdomen stretching and growing taut, the pale skin behind them slowly becoming visible. Her belly groans and rumbles, the eggs shifting and clacking into each other inside her. She begins to writhe, arching her back and straining her bonds near their limit. Still, the expression on her face is one of ecstasy and arousal.

"AaAAAaahh! W-why does it feel so-" she interrupts herself with a sudden piercing shriek of pleasure as she hits a growth spurt. Her clutch is impossibly large now, larger than any dragoness has had naturally. He wouldn't be surprised if she could barely touch the ground, were she on her belly.

"-GOOD!" She finishes, a shudder running through her as she presumably orgasms. She seems to calm down then, and the growth slows at last. The black dragon nods, pleased with his handiwork. He is about to jot down news of his success when abruptly the dragoness begins thrashing against her restraints, a look of panic and urgency on her face as she starts to hyperventilate.

"Hhahh... Ahh.. oooOOOoHHH!" She roars as a ripple crosses her belly, and with a mighty 'snap!', her hind legs are free of their bonds. And just in time too. She spreads her legs wide and brings her knees up to either side of her belly, clenching and unclenching her claws as another contraction hits her. Something shifts inside her, a visible bulge from the outside as it slowly slides through her birth canal and presses against her sex. The noises she makes are incredible as she passes the first egg, stretching impossibly wide as she gives birth to the larger dragons brood. The first egg is followed by another, and then another with little sign of stopping. Still, her belly does not seem to deflate, as if it producing eggs as fast as she can lay them. Oddly, she doesn't seem to mind, far too lost in the depths of her pleasure to offer any arguments.

"Oh. Well that's interesting." He says, unable to draw his gaze from her to double check his notes. He is very aware of his now painful fifth leg, who finds this scene incredibly erotic.

"Perhaps I mistranslated a step."