Twilight let out soft moans as she sped up her hand movements, panting and sweating as she masturbated as fast as she could, all pretense of discovering new information thrown completely out of the window. A couple of minutes later Twilight bit her lip to stifle a loud moan as she experienced her first orgasm as a human being, she couldn't tell if her orgasm was particularly intense because she was human or because of some other reason, but at that moment she didn't really care, she was too busy experiencing the pleasure coursing through every cell of her body. She let out a deep breath and allowed herself to fully relax on her bed, basking in the afterglow of a very long overdue orgasm, being so focused on this project had left here rare opportunity to find a secluded place to pleasure herself. Once she was fully recharged she sat up only to meet eyes with none other than Spike, who had just walked in upon her reaching orgasm and had been frozen in place ever since with two very large, very hard and very desperate, throbbing, veiny and unmistakably erect cocks.

Twilight tried to act casual about it and said "Hello Spike! How are you feeling?" The obvious answer to that would have been "horny", though that didn't seem like the best answer to give.

Spike was beyond embarrassed and just went "Um... I think that... maybe I should just go and-"

Spike was interrupted when Twilight, a bit louder than she meant to, just went "NO!" Spike stopped dead in his tracks and gave Twilight a quizzical and slightly confused look. Twilight cleared her throat awkwardly and said "I mean, no, no need to leave Spike. In fact you've actually arrived at the perfect time".

Spike was perplexed "I have?"

Twilight confirmed "You have. You see, being in this human body, I've decided that one facet of the species I need to study is the reproduction system and ever since seeing your... *ahem* ... equipment earlier, I've also seen fit to study the reproduction system of dragons at some point, but seeing as I'm here perfectly... available... and you're there perfectly... ready... I suppose you could say that this would be the best opportunity to kill two birds with one stone, so to speak".

Spike didn't want to get his hopes up, but he was pretty sure Twilight was actually asking him to have sex with her, he looked her in the eyes and said "So... just to be sure..."

Twilight already knew what he was about to ask and said "Yes Spike, I'm asking you to have sex with me, don't you want to have sex with me?"

Spike panicked "No no no! I do! I do! I just wasn't expecting it".

Twilight giggled "Excitable one huh? Come on Spike, get in the bed with me and we'll just... feel our way through it I suppose". Spike did as she asked and, still with two fully hardened cocks ready to be serviced, climbed into bed with Twilight. Twilight, still trying to make out this was for the sake of scientific discovery instead of the simple fact that she just felt like boning Spike, went "OK... I think it might be appropriate at first to um... lubricate you for ease of access to my... well, y'know the place where these things go...". Twilight may have been horny, but she was still a nerd. She took hold of one of Spike's penises and stroked it up and down, admiring its shape, he had a fairly sizable girth, not to mention a good amount of length, Twilight was almost nervous about the impending sex.

As she stroked one penis she took the other into her mouth and moved her head up and down as she gently sucked it, Spike simply groaned as his heart started thumping in his chest, feelings of deep-rooted lust and instinct coming to the forefront of his brain. Spike reached a claw forward and placed it on Twilight's head before applying some pressure and manually directing the speed and depth of her blow job, Twilight simply let out a small moan and allowed Spike to push her head up and down, obediently keeping up her affectionate sucking. After a minute or so she let Spike's cock out of her mouth with a *pop* and stopped stroking the other one, Spike wasn't too happy about this and actually snarled aggressively. Twilight rolled her eyes and said "Relax big boy, lay back so I can ride you", clearly not fully understanding that depriving a horny and hormonal dragon during the height of the breeding season was probably a bad idea, not to mention dangerous if things got out of hand.

Spike did as he was told as Twilight got on top of him in reverse cowgirl position, before she got started she looked back and said "For you to... well... let's say "finish", do I only need to stimulate one of your penises or-"

Spike interrupted her and in a deep gruff voice pretty much commanded "Both".

Twilight said "OK... let's give this a try", she gripped one of Spike's cock as slipped it into her pussy with relative ease, it was his second one where the problems started. Due to the size difference, getting one cock into Twilight's love tunnel was easy, but squeezing in a second one would be the difficult part. Nevertheless, Twilight wasn't put off and attempted to get him in, with no success whatsoever. Try as she might, Spike's other cock just couldn't fit in next to its twin, constantly sliding away from Twilight's hole. Twilight sighed and said "Sorry Spike, but it looks like- Ah!"

Twilight got the surprise of her life when Spike finally stopped being patient and rammed his second cock up her ass, gripped onto her hips and started pushing her up and down on his cocks. Twilight groaned, not quite sure if she was in pain or not, she was uncomfortable at best. "Spike... slow down..." she said, but her plea fell on deaf ears.

Suddenly Spike sat up and put her into a full nelson, shoving both of his dicks to the hilt in her pussy and ass and silently whispered "GET FUCKED". Which is exactly what she did as Spike abused her body like she was nothing but a rag doll, fire and smoke billowing from his mouth and nostrils. Countless hours and mind-shattering orgasms later, Twilight finally got relief as Spike blasted scalding hot cum into both her holes and practically threw her to the floor like a used tissue, both of them instantly falling to sleep.

• months later -

Spike woke up with a yawn, it was early morning, the sun was up and Twilight was under the covers completely naked and somehow managing to fit both of his cocks in her mouth as she blew him. As he looked down with a grin she took his cocks out of her mouth and said "Good morning master... how shall I drain your nuts today?"

Spike loved that the rough fucking he had given had somewhat broken her mind, it made it easier to mold her into the perfect sex slave, she hadn't even bothered to fix the magic mirror.

The End

Author's Note

Thank you osmar lael for this story idea! I hope you enjoyed it :)