Late Fees & Damaged Books.

Rainbow Dash wriggled and stretched out luxuriously on her cloud bed. Twilight had been as good as her word, and the armour spell had been left off for just long enough for her to finish herself off with a hoof, all the while her mouth and her nostrils had been full of the musky damp scent of her friend's juices. She knew that pretty soon she would need a proper bath, but for now she was content just to bask in the warm afterglow of the orgasm she'd been permitted. And after all the teasing and build-up it had been a pretty spectacular one. She was still barely able to move, and every so often a little shiver would make its way from the base of her spine all the way to the very tips of her wings.

A brief exploratory fondle with a hoof confirmed that once again her pussy was off-limits. She sighed. She'd known that it would be, but that still didn't make it any less maddening. She got up and stepped into her shower, letting out a little shriek as cold water hit her from multiple angles at once, then sighed happily as the heating kicked in, and the wet patches all over her coat were erased, and the warmth of the water soaked the tiredness from her muscles.

She soon felt back to her normal self, and as she stepped out and towelled herself off. Just because Twilight had gone nuts didn't mean she had to spend her whole day moping about waiting for her friend to come back to her senses. She preened her feathers as she considered this, and the more she thought, the more the possibility that this was just some elaborate and ill-conceived practical joke that had been taken a bit too far. She'd just have to talk to Twilight about it, somewhere out in the open, and sort it out.

Pleased with herself for having made this deduction, she finished waterproofing her feathers and gave her wings a little stretch before launching herself directly out the front door. She circled in the brisk morning air, a grin spreading across her face at the sight of Ponyville spread out underneath her, with the Everfree forest sprawling around over by Applejack's farm and Canterlot off in the distance. She spotted Pinkie Pie down far below her, frantically waving her down. She knew better than to try and ignore her friend when she was trying to attract her attention, so she went for the dive, wind whistling past her as she dropped, faster and faster, finally pulling out of the dive just in time to catch Pinkie's awed exclamation.

Out of nowhere a big sign with a nine painted in black numerals appeared in her pink hooves. "You lost the point for not having your theme music on." She explained, her tone apologetic.

"I'll remember that for next time, Pinkie. What's up?"

"Twilight invited me over for cupcakes, and I said, why just me? What if we all had some together, and she said sure, so I went to Applejack but she had already eaten and Fluttershy was feeding the rabbits, and Rarity said she had to have a business meeting up at Canterlot over lunch so she can't come either-"

"So it's just you, me and Twilight?" interrupted Rainbow Dash.

"Yup!" Pinkie nodded happily.

"Hey, uh, have you noticed Twilight acting strangely at all? I get the feeling she's playing a practical joke on me, which is weird, right?"

Pinkie shook her head and made an exaggerated "I'm deep in thought" kind of noise. "I think I'd notice if Twilight suddenly started playing pranks, I mean, ponies would talk, right? That isn't like her, not at all." Her expression went from serious to jubilant in the space of a heartbeat, and she continued, "but, like I said, nopony has mentioned anything like that at all, so she must be her normal self. Why, has she been playing pranks on you?"

"Sort of." She looked away self-consciously.

Pinkie's eyes lit up. "Ooh! Twilight got you? What'd she do? Was it the inky binoculars? Whoopee cushion? Was it the one where you get somepony to roll a coin up their face and it leaves a line? Was it the hot sauce cupcake?"

"Uh, yeah, that last one." Rainbow Dash prayed fervently that Pinkie Pie's interrogation was over.

She furrowed her brow and nodded, one prankster acknowledging another's skill. "Well, we have to prank her back! I still have to pick up the cupcakes from the bakery and then we can head straight over. We'll get her, don't worry, Rainbow Dash, just you leave it to Pinkie."

"No, it's okay, you really don't have to, I don't mind, I like hot sauce anyway."

"But she pranked you! We have to prank her back, that's how it works." said Pinkie Pie, slowly, as if explaining to a child something so self-evident that she was surprised it had to be said at all.

"No, really it's fine!"

Pinkie laughed. "You're too nice, Rainbow Dash."

"Yeah, nice, that's me." She laughed nervously.

They made their way to the bakery and then on to Twilight's tree library with no further mention of trying to prank Twilight, much to Rainbow Dash's relief.

She relaxed as Twilight greeted them with a smile and showed them through to where the table was set up. They sat and polished off the box between the three of them, leaving only one last cupcake sitting on the serving dish in front of them.

Rainbow Dash was too full herself for another, so the polite stand-off fell to just Pinkie and Twilight.

“You take it, Twilight, I think if I eat any more, I'll burst!” she giggled.

“Thank you, Pinkie, they really are amazing cupcakes.”

“That one's extra amazing.” And she winked hugely at Rainbow, who instantly began to panic. Twilight seemed to miss this little exchange, and before Rainbow Dash could do anything about it, the cupcake had been snatched up in a little telekinetic field and hovered over to Twilight's mouth.

The first bite had barely been swallowed before her eyes started watering. She waved a hoof frantically in front of her mouth in a vain attempt to cool off her burning lips.

Pinkie burst out laughing as Twilight ran off full-tilt to the kitchen, sticking her head straight into a bucket of water. Rainbow allowed herself a quiet chuckle as well, the look on Twilight's face as she bit into the cupcake had been too funny, and Pinkie's laughter was just too infectious not to join in.

Twilight returned a few minutes later, a sheepish smile on her face. “Good one, girls, you really got me with that one.”
The rest of the afternoon was passed amicably enough, the three swapping stories and jokes as minutes turned to hours, and almost before they'd noticed the afternoon was early evening.

“I'd better get back to the Cakes, they'll need a hoof with getting the bread ready.” She stood up and stretched a little. See ya tomorrow, Twilight, so long Rainbow Dash!”

As Pinkie trotted out the door with her usual bouncy gait, Rainbow grinned to herself and got up to leave.

“So,” Twilight smiled, “have you got an answer for me, little miss prankster?”

“Oh, look, I told her not to, but she got the idea that you were pranking me and you know how Pinkie gets...”

“And where would she get an idea like that?” Twilight's voice was quiet.

“I, uh- listen, Twilight this is all just-”

“Just what, Rainbow?” Twilight smiled sweetly.

The pegasus was tongue-tied, nothing she could think of sounded right.

“Never mind all that,” Twilight continued, “we can deal with your bad behaviour after you give me your answer.”

“My, uh, answer?” Rainbow Dash stalled for time. Her friend's ultimatum had almost completely slipped her mind with all the fun they'd been having all afternoon.

“You know,” Twilight's tone was playful as she advanced on the increasingly anxious pegasus, “our little arrangement. You haven't forgotten? Do you need a reminder?”

“No, I remember.” she swallowed, the noise strangely loud in the silence of the library.

“So, let's hear it. A month of torment, or a lifetime of happiness as my plaything?” Her horn glowed, and the lightest of touches stroked down between Rainbow Dash's hindquarters.

She shuddered at the touch, and felt her tail lift, a slight breeze tickling her as the magical presence stroked up and down along her folds. “Y-yes, please Mistress! I can't take this any more, just take me!” Her pleas all came out in one breathless rush, her eyes pressed shut and a burning in her cheeks, more turned on and embarrassed than she'd ever been in her life.

The magical touch receded, and she groaned, feeling keenly its absence. “Mistress?”

“I'm glad you chose right, I was a little worried that you weren't into this, and that I'd made some sort of mistake about you.” Twilight smiled wanly, and her horn flickered into life again, the resulting tendrils of magic brushing all over Rainbow's body.

Twilight was beaming at her. “I'm so glad. Stay right there, I've got a little present for you.” She trotted away with a spring in her step, returning barely ten seconds later with a small box. She opened it, and Rainbow felt herself being straightened up and her mane brushed lightly to one side as a little band of leather with a silvery medallion looped around her neck, fastening around the back with a barely audible click.

“It has your name and your cutie mark engraved on it,” Twilight informed her, smiling happily as she straightened Dash's mane back into place, and adjusted the collar so the little circle of silver caught the light.
“Isn't this a little too much?”

“It's magic,” answered Twilight matter-of-factly “Nopony else will even notice it unless you mention it to them. Now, stop sulking, I still haven't decided how to punish you for that little prank earlier.”