She wanted to be humming, but all she did was grumble. Her head on her table, Twilight's magic still lit up and with a little telekinetic mastery she dropped her current tool and reached for another. She was two days in and still having a great deal of frustration.

The current tool didn't work either. She allowed herself to fall backwards and with a little wiggling the thick silicone dildo plopped onto the ground as she levitated three more up for her to inspect. "Too small, not enough bumps and ridges.... Electric?"

She levitated the third one in closer to inspect before flipping it on and nuzzling it up against her sopping wet folds. She prodded it, smoothing up and down the length of her slit feeling it tingle and tease as it pressed against her clit. She dragged the tip from top to bottom and back again before slinking it a little lower and feeling her labia part. A little more pressure and her fluids let it simply glide right in. She mentally went over the checklist. It was new, it felt good, there was a soft curve to the length and this let her really grind up inside herself, getting in better than most places she had been hitting thus far.

Though she sighed and her magic withdrew the toy. "Not long enough, not enough girth, and its still a lukewarm piece of silicone. I need something... better... something..."

She stopped, looking back deeper into the castle. A thought crossed her mind but she swatted at it angrily. "No... What happens in my own private time during my heat is my own damned business..." She growled and sat in silence. She needed something big anyway. She was aching for something to really make it difficult to sit down for a week. It wasn't like the teasing thought in her mind would work anyway.

Growling in aggravation she grabbed one of the larger toys from the box and slathered it in her juices before pressing it against her ass. Biting her lip hard she pressed and tried to relax her backside. The ridges and pointed tip made the entry a little easier and despite the fact she was acting out in extreme sexual frustration, the moment the thick member penetrated she gasped loudly. She had strayed from the 'backdoor' play because she figured it would be a tad painful. It wasn't that bad but she needed something rough, and this was almost there. Gritting and grinding her teeth she pushed it in deep and felt her own flesh stretch as she moved it. It was going pretty good but, sadly it still just wasn't enough.

Taking it out, she tossed the toy onto the floor and growled loudly. She looked over at the toy as she sat there NEEDING more but unable to give it to herself. Her eyes drifted over the label on the dildo and it just made her loins stir even more. "Kirin model... Get a little dragon in you...."

She huffed annoyed before she grumbled and resigned to it. Not even believing her own actions, her magic swept up all the toys and shoved them back into her box labeled 'experimental library systems'. Her lips parted and she tried not to sound too stressed. "SPIKE!... Can you come here for a moment..."

It was a little ways later before Spike bumbled in. "What is it? I thought you wanted to be alone for a while..." He edged his way in and could tell something was off but he wasn't quite sure what was going on.

"Ok... now Spike... this is going to sound kinda odd, and I need you not to make a big deal out of it... ok?" She shot him a glare and he looked to be about to ask a question but instead he nodded. "Ok... Goodness, there are dozens of ways this goes down. Look, I need help with something, and I need you to be my assistant on this. But I'm going to have to ask you to keep it quiet ok?"

He smiled, still a little put off by the wording but he was still eager to please. "Oh... sure, what is it? New spell? Research? A friendship problem?"

Twilight groaned hoping to Celestia's giant white ass that she wasn't making a mistake. "Just... just hold still for a moment."

He nodded and she looked around just to make sure nopony else would interrupt. Binding the doors with a powerful magical lock she turned to Spike with a look that made him extremely worried. But Twilight managed the spell quickly and efficiently.

Spike nearly leaped out of the way when the blinding flash drowned out all color and overwhelmed his sensor perception. It didn't hurt but his whole body felt odd, extremely odd. Like he was being stretched and electrified ten times over until finally he creaked open his eyes.

He had fur. Spikes eyes went wide and he felt off balance. He had fur, practically a mane, not like ponies, but almost like a lion. He looked over, feeling himself with what oddly looked like hooves. He fell onto his rear then rolled onto his back still concerned and frightened. "T...Twilight?... what the heck did you do?"

"Shhhh!... ok... look, I turned you into a Kirin, now I need you to be cool about this ok? I BADLY need this. I'm sorry I just really need this..." She came closer and posing over him he looked up, a little more frightened by the look in her eyes.

"Wh... what?"

She leaned in and his eyes shot wide as her tongue washed over his testicles and with a little bit of magical help his length began to sprout from its sheath for her lips to delicately suckle on.

"T...Twilight!! wait... wh...what?"

Her eyes glared up at him as her mouth continued to cup around his growing length, suckling and swallowing she even impressed herself as the rapidly growing length slid down her throat as it expanded. It wasn't until she could feel it swelling over the size of her airway that she pulled back. But, finally out of her mouth and throat, she leaned in letting its majesty flop against her face.

It was perfect, she could feel the heat radiating off of it, she could even feel Spike's pulse, and she knew it would be a bit of a workout but she would get it inside her. Drunk of the little taste she got she licked up the length one more time before she stood up and grinding her teeth, so too did she begin to grind her marehood over the oddly shaped and large member. Spike fussed and she responded with a quick. "SHHHH!"

Whimpering he finally spouted. "N.. no! wait... Twilight.. this... this is just... can.. can I wait?... its just..."

"Shush!... I really REALLY need this..." She moved further up letting the point of his new cock part her labia before she put some weight into it until it notched into place and she shivered at the feeling of the girth stretching her. She was well past ready for it, looking down between her legs she could even see where his length met her and she smiled at her fluids rolling down his cock.

Racking his mind in a last ditch effort he spouted off quickly. "I could get you pregnant!!"

"I have spells for that... just... be cool with it... trust me, its much better than you think..." She looked back and remembered it was the exact same thing Celestia told her, and Twilight didn't complain afterwards.

Spike opened his mouth to object but she dropped her weight into it and with a wet juicy pop his length sank deep inside her. A deep gasp escaped her mouth as Spike just moaned loudly.

Just like Celestia, her magic reached out and tapped into spike preventing him from cumming before she was done. Her hips went to work, bobbing up and down, his girth was impressive but she was desperate and just shuttered at the feeling of his member destroying her nether regions.

It was as sloppy as she could possibly conceive of. Her fluids alone already were pooling up under spike, his cock in her was already tight enough to almost hurt but she was approaching her first climax. Her jaws went tight and she rocked her body against his length, taking a peek at him, she smiled noticing she had taken to it just like she did with Celestia. The fear was gone and he was exploring the euphoria.

She was already on the verge, feeling all his heat, hearing and feeling his hot breath on her skin, she could even feel his pulse going rampant as she plunged herself into it one more time.

She dropped the spell on his cock and instantly she heard him moan uncontrolled as his length crammed against her cervix and the cum blasted into her. It was an excessive flow and she lost herself, drunk in the overflowing cum dribbling out of her. She stood up off him then with one more hungry thrust, she struggled and forced his length entirely past her lips and down her throat. Pursing her lips around his shaft, she suckled the cum clean off and out of his length getting a nice belly full before pivoting and letting her front legs fall out. Leaving her rear up high and her aching pink practically gushing cum into a puddle below her.

Twitching and moaning, she was quite content, lost in though and mumbling to herself, her eyes began to close when she felt hooves around her, pulling her hips in as a cock pressed against her again. Without much warning it pushed in and she could feel spike as he grunted away, striking deep inside her.

A smile crossed her lips and she whispered out. "Good boy..."

Had there not been a puddle of her juices, it would have been a puddle of his cum, had it not been for that, it would have been their sweat as just one more time, Spike came, He would have been shooting blanks after the fourth time had Twilight not helped him out with some magic. This was the fifth time in her ass, she beamed happily in the glow of pleasure. She had been happy with round one, but each round after just put her more and more past good.

Her afterglow was more than just present, it was currently like an ascended state of being. She could feel him starting up again, but only slightly surprising, the little Kirin simply 'poofed' back into a dragon.

He didn't waste much time, making his way over, the small reptile member slid past her lips and she helped him just one more time.

She barely had the energy to swallow the load after she playfully opened her mouth for him to see his seed cupped on her tongue. "Spike... you...y...you really are... th...the number one assistant!"

He smiled and fell back against her, exhausted. "Twilight... t...thank you... holy Celestia... I wouldn't have struggled if I knew..."

She gave a weak laugh and nodded. "Yeah, sorry, but like I said, I REALLY needed it..."

"It's not too weird if I tell you that I'm available from now until forever right?" They both laughed and they sat for a moment before spike stood up and wobbled over to the door. "Imma shower and fall asleep, this... this was just amazing... Where did you learn a birth control spell anyway?"

Twilight smiled. "Oh... Celestia teaches me a lot you know..."

"That's cool... I just hope you have it handy, it would be fun to spontaneously just have some fun."

Twilight struggled to get her hooves under her and mumbled happily. "Yeah, it takes a little while to do... but its great... great for times like this."

"Takes a while to do?... oh so you did the spell before I got into the room?"

Twilight's eyes shot wide. "Oh fuck...."