Fucking up reality some more.

Isaac's whole body was shivering with the giddy glee of a power trip combined with the natural anticipation that precedes sex. Just breathing made him aware of his whole body and his now enhanced cock, which was... It had to be at least two feet long if it was an inch, right?? Maybe even pushing straight-up 30 fucking inches. It was an absolute monster, straight out of his most unrealistic fantasies, and now he could feel every nerve ending as it relayed stimulation back to the pleasure centers of his brain.

"It's going to be a trick to get this monster inside of me," Celestia husked in that maternal voice of hers, then winked. "But I'm eager to try."

That gave Isaac an idea, and he was too far gone to ignore the impulses of his id at this point. "Y'know, when I started to figure out that I was having an effect on ponies, I went to Twilight's castle library to read up on a few things..."

"Oh? I hope you didn't spend too much time in the erotic fiction section," the alicorn demigoddess teased.

And now he had yet another idea to supersede the first one! "Now that you mention it, there was a lot of smut along a particular theme... Is it the ultimate fantasy of every sexually active being in this world - besides me - to be part of a massive harem, potentially millions upon millions strong, all dedicated to one guy?"

Back in Ponyville, Rarity, of Carousel Boutique, was taking some time during her lunch break to catch up on her latest trashy romance novel. Not that she considered them such, but she knew their reputation and was no fool. This particular book, though - the author had her absolutely hooked. She'd been thinking about it the whole morning, dying to get back to it. Her eyes devoured the text as she sipped her tea and took a bite from her sandwich, her blue unicorn magic helping her multi-task.

"Oh, my lord Midnight!" swooned Epona. "You have brought countless planets under your righteous rule, and the galaxy harmonizes your name as they call out to you in pleasure! You have your pick of the universe's most beautiful, amazing, powerful concubines, and I'm just a nopony from a backwater village! You don't have to pay any attention to me. I could spend the rest of my life watching you via hologram, fingering myself silly, and I would die content and fully satisfied!" In her voice, there was no mistaking her sincerity - she meant every word.

Midnight hummed in thought, the sheer bassy rumble of his voice reverberating in Epona's core. The wall of night-black muscle that was his bare chest rose and fell, sweat glistening in the dim, romantic light as it traced the shape of his abdominals. Outside the palace, the fireworks from the Midnight Festival burst into color once more, reflected in Midnight's deep, soulful eyes as they stared into Epona's own.

"I'm so glad you care about me, that you put me first," Midnight finally answered. "You're right, I could go to Titula VII and have all the titfucking orgies I want. I could visit the Council of Fellatrix and have my cock orally worshiped from now until the sun goes supernova." He reached up to Epona's face with one giant, powerful hand and, with the most surprising delicateness, brushed the tears from her cheek. "But nopony out in the universe can replace what you mean to me, with your unique personality and undying affection. In fact..."

He began to kneel down. Epona's heart felt like it might explode out of her chest! "M-My lord Midnight!" she protested. "Y-You can't! You're already arranged to be... The political consequences...!"

"Fuck the politics," he growled in a rare moment of brutish candor. "Epona... Will you be my First Concubine?"

"Oooooh!!!" Rarity squealed, her hooves tapping excitedly on the floor of her dining room. What a plot twist! Then she glanced at the clock and realized that she needed to go back to work soon, and she slumped in her chair. "...Why can't a male like that show up and take me... and my friends, and all of Equestria while he's at it...?"

She reached a slender hand between her thighs. She couldn't focus on dresses with such fantasies on her mind! Work could wait a little longer.

"Wouldn't that be something~?" Celestia teased, not betraying the answer just yet. She planted kisses on the underside of his cock, making Isaac gasp and shudder each time.

"Dayum..." Even Isaac had to marvel at what he was creating here. In less than an hour, the world had gone from a relatively chaste fantasy land of magic to his own personal porn. And he wasn't done yet.

Now, what had he been plotting a moment ago...? Oh, right!

"G-Getting back to what I read, though... Is it true that the beings of this world are naturally stretchy and can take any size of sexual insertion inside their holes?"

There was no immediate visible change, but Celestia's eyes held an even stronger hunger as they gazed upon his massive human dick. There was no doubt about it - she was going to take this huge cock. "Such a clinical way to describe it. Were you reading medical textbooks?" she teased him some more, pulling back from her kisses and stroking his shaft as they chatted.

Isaac grinned sheepishly. "I... did a lot of writing back home. I have a bad habit of trying to be very precise in my word choice, I guess. Not the sexiest character trait, I know." It also helped for this reality-warping power, but he sure as hell wasn't going to say THAT out loud.

"I think it's kind of cute, for what it's worth," Celestia remarked. "There's something to be said for a bit of a nerd with a massive, studly cock and eyes bigger than his stomach, hmhm."

Yep, that was pretty much the trajectory here. Not that there wasn't room for improvement. "Are all of you natural size queens? Does the size of my big human cock and balls fill you all with awe?"

That caused a more immediate change. Celestia's smug confidence was instantly replaced with a wide-eyed stare, her big colorful pony eyes straining to take in every detail of his oversized tool. "Fffuck..." she breathed, leaning in and pressing his shaft against her face again as she stroked it, slower and more reverently this time. "I've only ever seen full-sized dragons with bigger tools... but even they didn't care to really use them. You're the first real male in millennia who wants to fuck, and you've got this... mmmgh, big... fucking... cock...!" One of her hands reached down to stroke his swollen, soccer-ball sized testes. "Hngh, and these big beautiful balls, too...!"

It was hard to focus under such intense affections. It was all Isaac could do to stay up on his knees and not fall back onto the bed and just ride it out. He still had changes he wanted to make. "Big human cock is just better in every way, huh?"

His cock tingled, surging with vigor. Isaac wasn't sure what that feeling meant, but Celestia seemed to fall deeper in lust with his cock. "Not even a competition...!" Celestia husked, practically drooling onto his shaft. "Please, Isaac, tell me what you want, I'll give it to you...!"

"Sorry, just a few more questions that are bothering me," Isaac said with a chuckle, deeply amused and aroused by how **** this immortal sun goddess was getting. "Is it true that the average, uh, proportional breast size in this world is... three times the size of their owner's head?"

As much as Isaac might have liked to watch some breasts expand, once again there was no transition. One moment, Celestia was busty enough in a mundane way to make every model on Earth envious at her natural beauty. The next, she was bearing heaving mountainous mammaries the size of beach balls that jiggled and swayed with every breath. The red straps draping down from her collar just barely managed to reach down and give her nipples some modesty, and even then her pink areolae peeked around the sides.

Before Celestia could respond, Isaac added in an almost trembling voice, "And- And you're exceptionally and extremely busty even by those standards, right?"

Strangely... Celestia didn't change any further.

In fact, Celestia didn't look terribly excited about having this pointed out. "My gift and my curse... I usually keep them magically reduced, but I'm not surprised you found out..."

That wouldn't do. Isaac started rambling the moment he sensed the pain in Celestia's voice. "Breasts in this world are magically convenient, right? Isn't it true that they don't weigh you down or give you pain, that they always stay perky and round and buoyant with just a hint of sag, they don't affect aerodynamics or your ability to move, and they're basically invulnerable to harm? Aren't you extremely proud of your breasts?"

Isaac's lower body was instantly buried in white marshmallow softness. Being so close to Celestia's body in this moment, there was no easy way to tell exactly how huge her tits were, but they were straight out of his most depraved hyper-breast fantasies, for sure. Celestia's top changed, doing away with the red cloth strips that would have covered her nipples - a futile effort now. Instead, she wore silky golden sleeves that accentuated her arms, and her enormous breasts were totally exposed.

"Is it that obvious, human~?" Celestia purred, back to her smug, sexy demeanor once more. She leaned in, and the ocean of white breast surrounding him shifted past his hips and legs. "I see you've done your 'research'... but how about we put that theoretical knowledge into practice~? Unless you've got more questions to tease me with~?"

Isaac grinned wickedly. "Just a couple more... Is it true that breasts in this world are orgasmically sensitive and can induce lactation with enough stimulation? And do the sensitivity and milk production scale with size?"

Celestia let out a moan, and she reached out to squeeze her breasts around Isaac's body, smooshing them together until they pooled up nearly to his shoulders. With her 10-foot-tall body, increasing the average, and then putting her so high above the average without physical or biological limitations... Her tits were fucking enormous.

Her body was his playground.