“I think you’ve got it, Tenten,” Choji told his friend with a smile, chuckling as the bun-haired woman raised her arms and cheered. “I take it you’re happy?”
“Damn right! I was beginning to think it was going to take me years to get this Expansion Jutsu down pat.” Tenten stretched, working the kinks out of her limbs. “And you were able to use it when you were just a genin; I have a whole new level of respect for you, Choji.”
The big-boned man blushed a little. “It’s not that impressive. I had a whole clan teaching me from the time I could walk, and it’s practically built into our bodies. For you to pick up this fast is impressive in its own right.”
Tenten laughed. “If you say so. And now that we’ve both complimented each other, let me thank you again for teaching this to me. I know how important clan techniques can.”
Choji waved her off. “It was my pleasure. Besides, it isn’t as if you didn’t pay me well for it, and you’ll never be able to use it to the same extent as my clan and I. Honestly, I’m still not sure why you wanted to learn it.”
“It’s a surprise,” Tenten told him with a smirk. “Something of a personal project for me; if all goes well, you’ll find out soon.”
Choji stared at her for a moment before smiling. “All right then. Best of luck with your project, whatever it is. I hope it’s something fun.”
Tenten’s eyes glittered. “Oh, it is, Choji. Believe it.”
This should be private enough, Tenten decided, taking a moment to admire the view from this seldom used training ground. It was out of the way, and with most of the ground comprised of stone and little else, it didn’t offer much in the way of variety. Hence how little it was used, making it perfect for her experiment.
Quickly stripping out of her clothes and taking a deep breath to calm her nerves, Tenten focused on the Expansion Jutsu; this time, she channeled her chakra to a very specific body part.
And slowly but surely, her butt began to get bigger. And bigger…and bigger…and bigger…
Panting, Tenten stopped the flow of chakra and craned her head to see behind her. A blinding smile lit up her face at the sight of enormous ass sticking out behind her. She wiggled it, almost falling to the ground at the difference in her balance. But her ass cheeks wobbled and jiggled wildly, like a gelatin mold in an earthquake.
“It worked…IT WORKED!” Tenten shouted triumphantly, spanking her expanded butt with one hand, watching with delight as the ripples spread out from the impact point; it was as if a rock had been dropped in a pond.
No more getting overlooked, no more feeling like I can’t compete! She thought gleefully, reveling in her new attribute. Now I’ll be the center of attention, and this is just the start! I can can enlarge my tits too, and all my other body parts!
Tenten laughed aloud, repeatedly spanking her butt as she crowed, “That’s right, world! No one can handle this huge, fat–”
When the huge erection plowed right into her asshole, Tenten froze for a moment, her mind overcome with the shock of it. Face instantly blushing, she bit her lower lip as her eyes threatened to roll up into her head. “FUCK!!!”
“Oh, I wouldn’t say ‘no one,’” came Naruto’s amused, and aroused voice. “You just have to have the right tool for the job, and,” his cock pulled back slightly, only to slam back into her ass with full force, “know how to use it!”
“OH FUUUCK!!” Tenten screamed as her asshole was reamed; stretched to it’s absolute limit, all she could do was take it, her body and mind reeling from the intense pain and pleasure hitting them. “N-Naruto?! What the hell are you dooooooing?!” She finished with a shriek as he began to grope and spank her ass himself.
“Eh, I was just out for a walk when I felt your chakra being built up,” Naruto replied casually, burying his dick all the way into her ass and grinding it around. After waiting for Tenten to stop squealing, he continued. “I’m really impressed with what you came up with, but when you started claiming that no one could handle an ass this size..”
He chuckled, grabbing onto the aforementioned ass and using it as leverage, to fuck her harder and faster. “Well, I never could resist a challenge.”
“AAAHHH! MMMMPPPPHHH! NNNNGGGGHH! OH HOLY-!!” Tenten had never been fucked like this before, certainly not by a cock this big and with her ass equally huge and sensitive. Her body was hot and sweaty, and it felt like her mind was melting as well. “OH SHIT, I DON’T THINK I CAN-! MOTHERFU-!!”
“Wow, already?” Naruto asked in surprise as Tenten came with a shriek, her ass tightening and spasming around his erection. “And you said no one could handle your new ass; looks like you need some more training. Lucky for you, I have some free time today!”
Tenten barely heard his teasing and taunts, too preoccupied with the orgasm slamming her body. This time, her eyes rolled up completely into her head, her mouth dropping open and her tongue lolling out at the same time.
Then Naruto somehow managed to increase the speed and power of his thrusts even more, and Tenten’s whole world became his cock, her ass, and the orgasms slamming into her, one after the other. She could hear herself screaming and begging; whether she was pleading with Naruto to stop or was desperate for more, she wasn’t sure.
When Naruto finally came in her ass…well, the world went away for Tenten for a while, as the pleasure simply overwhelmed her. The next thing she knew, she was lying on her stomach, gasping for breath, and feeling Naruto’s cum leak out of her butt and trickle down her ass cheeks and thighs.
“Well, this little break turned out to be a lot more fun then I thought it would, so thanks for that, Tenten!” Naruto told her cheerfully. He didn’t even have the decency sound the slightest bit winded, the bastard. “That’s a really great experiment you have going on; I look forward to seeing what you come up with later. See ya around!”
And then he was gone, leaving the bun-haired brunette laying on the ground, slowly collecting herself. Tenten pulled herself to her feet, eyes burning with determination.
Oh, you had better look forward to it, Naruto. Next time, not even you and that enormous dick of yours will be able to keep up with me!
(Story by User: S22132)