Someone found the spare key
Vacuum Tube gasped as the stallion on top of her suddenly pulled away from the kiss, then, to his surprise, he rolled them over, putting her on top! "Go ahead, try to pull off, else I'm breeding new foals into you~" growled the shadowy pony below her, his glowing eyes cutting into the darkness.
As she carefully sat up, helplessly clenching around his cock as it shifted and throbbed inside of her, she couldn't help but wonder how it even got this far! It had all started when she walked into her apartment for the night, only to be pressed against the wall, engaged in a horny kiss with the mysterious stallion...
Then, the kiss had only grown more and more heated, and she found out he was naked when his hard cock pressed against her! She had resisted when he took off her shirt, pushing back against him, but each time he removed an article of clothing he turned up the heat, kissing her harder, groping her body, grinding his cock against her. With her willpower rapidly eroding, she found the stallion stripping her until she was left in nothing but her panties, the thin fabric struggling to restrain his cock as he ground it against her soaked folds while making out with her.
She tried to resist one last time, but the stallion shoved his tongue down her throat, making her shudder, then he slid a hand into her panties, worming his fingers into her soaked pussy as he began to roughly massage her clit. She just melted when he started doing that...
Oh, and then he had shoved her onto her bed, while sliding down those panties... and then he dove that throat-bulging tongue of his into her marehood! By then, the poor mare had been too badly turned on to stop herself from cumming, and when she did, he waited until she was sinking into her afterglow to slither on top of her, plunging that massive, throbbing, leaking cock into her...
And then, the rutting! He'd wasted no time in holding her to the bed, plowing her like the slutty mare she'd been a decade ago while muffling her moans into another one of his throat-violating kisses. The entire time, his cock was firing off steady gushes of precum, and their heated, increasingly sweaty sex only became messier and messier as it splashed back out of her onto their hips and the bed.
But back to the present, she had just began to feel him flare when he'd broken that kiss... She had to struggle to remember what he had said to her, then she meekly asked "P-Pull off?", shuddering as his cock twitched within her. She tried to move, but she soon felt that his inky, shadowy magic had trapped her legs, cementing her knees to the bed as she straddled his lap. She could pull up, lifting herself until his throbbing flare scraped at her entrance, but... it was useless, she could only sink back down onto his cock and moan as his words burned hot in her head.
She could feel him flaring, his balls pressed against her, he had to be close! But she didn't want to get pregnant again! She met his eyes, and her blush burned hotter as she saw the smirk on his snout, those sharp teeth glinting in the moonlight. "I-I can't..." she said quietly, lifting her hips in another attempt to escape as she helplessly clamped down tight, her pussy trying to keep him inside despite her wishes.
Each time she rose in his lap, pulling off of his cock, she desperately tried to pull all the way off of him, whimpering and gasping as she felt the entrance of her marehood squeezing and gripping at his flare, so close to popping out of her. And yet, each time, she sank back down with a helpless whimper, feeling her own orgasm approaching as she ground down against his cock, soaked outer lips mashed against his crotch as his flare soaked her cervix with his precum.
As she sat back down again, she stopped, panting heavily as she clenched around his cock. She could feel his flare, pressed against her cervix, slowly filling her womb with his precum... she whined a bit, and she lifted her hips again, feeling her looming orgasm return almost right away despite the brief rest. Oh, that naughty stallion! He had to know how good it felt as she tried to pull away, tightly squeezing that leaking flare with the most sensitive portions of her marehood... he had her riding his cock and bringing him to an orgasm, and she couldn't stop!
As she prepared to try again, the stallion reached up, firmly grabbing both of her heavy boobs. He began to grope them, rubbing her nipples, squeezing them in just the right ways... as she lifted her hips to their highest, she grabbed onto his arms, making a pathetic attempt to remove them from her sensitive boobs as the added pleasure sent showers of lustful bliss through her. He knew just how to squeeze them, just how to rub her nipples to send tingles down her back...
As she held herself there, she strained, her legs quivering, and she gasped sharply as she felt his flare pop out of her marehood! It was out! But now that his thick flare had escaped, all it took was a sudden upward thrust from the stallion for his cock to firmly grind against her clit and then pop back inside of her! Even though it only brushed the nub for a moment, that was all it took.
Vaci cried out as she felt her orgasm take hold, and while she tried to resist, tightly squeezing the flare as she began to cum, her legs collapsed, and she dug her nails into the stallion's arms as his cock plunged back inside of her, their hips meeting with a loud, wet slap. As she fell onto his cock, all she could think of was the way it sank into her, the finality of feeling that flare push deeper, deeper, right up to her womb.
As her orgasm began, his magic wrapped around their hips even further, binding them together as she helplessly made a failed attempt to pull away again. Her voice shaky and pleasured, she wheezed a "D-Don't...", but it was too late. As she realized she couldn't budge her hips anymore, she felt the first strong blast of cum slosh inside of her womb, and she squirmed and cried out as she felt her orgasm intensify even further.
As the stallion properly entered his own orgasm, he rolled them over, pinning her back down to her bed again. It only added to the fire of her lust, making her latch onto him and moan onto his neck as she began to grind against him. Soaked in sweat, the two ponies rocked against each other, tightly embracing as they rode out their orgasms, Vaci unable to stop herself from milking the stranger for everything he had while the stallion eagerly pumped everything he had directly into her womb, his flare preventing any from leaking back out.
It wasn't until she began to come down from her orgasm that she realized he was still pumping his cum into her, bulging out her belly, and she groaned as pushed up against him, forced to endure the excessively lewd sensations of his cock pumping fertile cum into her without the fog of orgasm to distract her. She felt the final few pulses of cum peter out to the same steady flow of his precum, and his shaft calmed down a bit, returning to gentle throbbing instead of powerful twitches. Her belly was now squashed against him even more, and she couldn't stop herself from repeatedly clenching down on the still-throbbing cock as she sank into her warm afterglow.
"Mmmhhfff... y-yyoouu... f-fuckin..." she grunted, but he silenced her with a kiss and a sharp buck of his hips. And by now, she didn't mind, she returned his kiss with a blissful moan as she ground up onto that delicious cock of his~.
A while later, after the two ponies had fully ridden out their orgasms, the stallion slowly rolled them back over, putting Vaci back on top as his dark magic slowly melted away, some of the bulk disappearing from his body. She was thankful that his cock shrank slightly as well, he was big in his darker form.
Polaris was the first one to speak, the blue stallion smiling up at her as he said, "Have fun~?"
She snorted, then she said, "you were wonderful... even if you are such a kinky bastard~". She teased, nuzzling him a little.
Polaris just ran a hand through her mane, saying, "I dunno, sounds like someone was cumming pretty hard~".
Feeling her cheeks burning, she poked his snout, saying, "Well, I wasn't expecting... a lot of that, heh..."
Smiling a more gentle smile, Polaris said, "well, I'm really glad I did good... I know it's hard to ask somepony about a fetish like that~".
She giggled, then she snuggled down against him, making sure his shaft was buried as deep as it could go before she kissed him. And as she did, Polaris kissed back, wrapping his arms around the mare as the moon illuminated them.