Twilight: (Looks at her sweaty and muscular body in a full body mirror) Ever since I've accepted Luna's offer to be her bodybuilding student and workout with her, I've loved working out and seeing my muscles grow right before my eyes. The veins on my pectoral muscles now showing through a tank top that Luna gave to me as a gift after I was done working out for the first time, albeit a tank top that I've ripped so that I could see my abs. My biceps, quadriceps and inner thighs pulsating with veins, the musk of my sweat on my muscles reaching to my nose increasing the very arousal of my muscles that I'm trying to contain and a micro-thong that I can break with just a flex of my vagina muscles. (Notices the sweat on her face) I didn't know that admiring my muscular body and talking about it in such a way would arouse me this much, .....I never though that I would get more aroused than I did last time.... (She starts to pant lightly as she slowly gives into her lust for her muscles without letting herself go too far)

1 hour later

As Twilight was slowly giving into her lust for her muscles, she saw on the full body mirror that her clit and nipples were fully erect. So she tried not to look at herself so that she can calm down, however she couldn't look away as more sweat was covering her muscular body and combined with the musk it was giving off, Twilight light pants started getting heavier.

"I can't....hold myself....BACK ANYMORE!!!!!" she screamed lustfully between pants and takes off her indigo shredded tank top and micro-thong revealing her muscular and now naked body.

Twilight starts flexing her pecs at a fast rate which caused the veins on them to grow bigger and more engorged with every flex. She was using her full body mirror to see her rapid pecs flex and she was loving every moment of it, Twilight was loving it so much that she started to flex them as hard as how fast the unicorn was flexing them. More sweat appeared on her face and was dropping from it like rain considering how sweaty it was, yet her pecs were the ones that are sweating the most. She was so mesmerized by her pecs flexing that Twilight didn't notice the Pr cum oozing out of her muscular vagina, which was getting very vein y due how pent up she was.

"My pectorals that are glistening in my sweat look so muscular, vein y and beautiful, and if I wasn't so enthralled by them, I would flex every single muscle on my body with the same speed and hardness as I'm putting into my pectorals" she said as she was now panting heavier with every passing second.

Suddenly she felt her vagina muscles clench and tense up, which is usually when Twilight would normally stop and catch her breath before her lust gets the better of her, instead she started to flex her pecs so hard and fast that she was trying not to give into the pain that it was causing. Twilight was now panting and grunting primarily and was doing so harder and faster with every passing second.

Twilight was able to focus long enough to see how muscular and vein y her vagina was and saw the pr cum that was coming out of her mare hood like a kitchen sink, this caused her to flex her pecs even harder and faster realizing what was causing her to flex like this.

"All of my life I had never known what is like to have an orgasm, especially since I didn't had sexual intercourse with any pony or masturbated, which resulted in me being pent up for 21 years. But when I became Luna's bodybuilding student and worked out with her, all of that pent up lust rose to the surface and I was holding it back ever since.....until now" she said and flexed every single muscle on her body insanely hard, including her muscular and very vein y vagina.

Cum was now gushing out of Twilight's vagina like a waterfall and looks at herself with a lustfully enthralled face when she saw that she was doing the very flex that Luna did on the day that made all of this possible perfectly. This caused her to have a sudden flashback of that day, which she didn't mind at all since she was having what Luna called a "sensation".

5 months ago at Twilight's Tree house

Twilight was downstairs sitting on a chair in her pajamas as she was waiting for Luna to come here, she had no idea why the moon princess wanted to talk to her about, but it sounded like she really wanted to tell her. So she checked the clock on the wall and it was 11:30PM, by the time she gazed her eyes back onto the door, she heard a knock on the door.

"May I come in Twilight?" the unicorn heard and knew who was at the door.

"You can come inside Luna" she answered and Luna teleport ed in front of Twilight without being too close to her.

Twilight was a bit surprised and confused when she saw her, she was bigger than when she saw her at the Canter lot Library, which was about the same size as Twilight was. She was wearing a black hoodie that seems to be doing an somewhat decent job at whatever she trying to hide. But just as she was about to analyze her, Luna snapped her fingers and Twilight was now looking at the moon princess's face.

"Are you the only one here?" she asked.

"Spike is sleeping over at Rarity's place and my owl is at Flutter shy's Cottage recovering from a cold" she answered hoping that Luna can tell her why she wants to meet her.

"That's good to hear, now instead of telling you why I'm here like I originally said, I'm going to show you" she said and takes off her black hoodie without breaking it.

What Twilight was seeing was something that she only read about in her books, she knew that Mare Bodybuilders have huge muscles and only have pecs due to working out their chest so much, but what she was seeing is Luna with muscles that make both mare and colt bodybuilders look puny in comparison. She should be disgusted by how strong and shredded the moon princess is like the ponies in those books, instead she was mesmerized at the sight of Luna's muscles. The thought of loving muscles on a mare caused her to blush, and she blushed even more when she realized that Luna was wearing nothing but a micro-kin and micro-thong.

"It's okay if you love these muscles, in fact, you shouldn't be afraid of the feelings that you are having" she said.

"B-B-B-B-UT a mare isn't suppose to love-" she was interrupted when Luna put a finger on her lips.

"If you love seeing muscles on a mare, then you shouldn't be afraid of it because of what other ponies say" she said and used her free arm to flex her bicep.

Luna's words rang through Twilight's head, which caused what Twilight was feeling to rise to the surface. Twilight puts one hand on the bicep Luna was flexing to confirm if she had started loving the sight of mares with muscles, feeling that bicep caused her vagina to tense and clench up. Luna removes the finger on her lip and hold her shoulder to hold her down so that Twilight won't fall off of her chair.

"Luna.....I....I've never felt like this before, this newfound love of muscles....the feeling...of lust that I've got just by touching your bicep is something that I never thought I would experienced...." she said having a hard time talking.

"What you have felt was a result of you gaining a sudden lust for muscles, and it's something that I also have, although not to the same extent that you have. ......But if you don't mind, could you use both of your hands to feel my pecs?" she said and stopped flexing her bicep while hoping to confirm that Twilight has gained a sudden lust for muscles.

Luna was taken by surprise when Twilight instantly puts her hands on her pecs and starts feeling them, but she loved what she was doing and flexes her pecs a little bit. A moan escaped from Twilight's lips which caused her to stare at Luna's pecs lovingly. Seeing this, she puts her right hand on Twilight's right shoulder and looks at her with a look in her eyes that seemed to cause the unicorn to stop what she was doing and calmed down completely.

"I know that you want to keep touching my pecs, but what I'm about to tell you requires you not to be lustful as well as having a clear head" she said and Twilight was now waiting for what Luna is going to tell her.

"Twilight Sparkle, I want you to be my student and show you how to gain the muscles I have acquired as well as workout with me. You can take your time and think about this, theirs no need to rush" she said and Twilight smiled happily over what she just heard.

"Theirs no need for me to think about this, I've love those muscles you have and I'll be happy if you to teach me how to get them! Besides.....I want to be able to control myself so that my lust doesn't get the better of me" she said without a second thought.

"Very well, tomorrow night, we begin your training. But don't expect to gain muscles overnight, it takes hard work and dedication to acquire even the smallest amount of muscle. So as long as you do everything I say and tell you to, you'll might be able to become more muscular than me" she said and to prove her point, she walks far away enough so that Twilight can see her and flexes every single muscle on her body as hard as she could.

Twilight was snapped back to reality when she had a 2nd Musclegasm which sent her hormones, lust and libido through the roof causing all of her body to be drenched in sweat and the musk of it to intensify to the point where she was driven insane with lust as all of her muscles are getting covered with huge and engorged veins.

"So much for not letting my lust getting the better of me, ah well, might as well enjoy it while I can before nightfall" she said in her mind and goes all out in her flex.

12 hours later

After her 15th sensation , Twilight had drank all of her cum to clean up any evidence of the events that happened here, which was something she regretted doing as her cum tasted horrible considering that her sweat had mixed into it. But she was happy about one thing, those 15 sensation's has increased the size and mass of all of her muscles by 30 feet, which makes her muscles 50 feet all around. It doesn't sound like much, but Luna's muscles are 40 feet in size and mass, this means Twilight is now 10 feet stronger and muscular than Luna who had worked out for 5 months just to get as strong as she is now.

Author's Note

this my first story on this site hope you like it