NSFW
Macrophilic content, mouthplay, unbirth, masturbation
Has My Little Pony: Friendship Is Magic-themed content

Starlight was working on some magical equations
The action of performing spells was fine for her, but formulating them was always a toughie
Beside her was Pinkie Pie, who was instructed by Twilight to watch Starlight in case she did anything…dangerous
Twilight was still in the castle, working on compiling all her friendship lists into one Friendship Omnibus
Pinkie Pie: Are you finished with the equation yet?
Starlight: No
Pinkie Pie: Is it a fun spell?
Starlight: That's up to interpretation
She was preparing an apple to be zapped with a shrinking spell that would minimise any object to a tenth of its normal size for 2 minutes
Of course she didn't tell Pinkie Pie this, lest she go nuts with the formula and decide to use it for something stup-
Pinkie Pie: What spell exactly are you working on!?
Starlight: Pinkie, mind if you stop asking me so many questions?
She prepared her horn on the apple, and a turquoise light was starting to emit from the tip
This time, it'll finall-
Pinkie Pie: Hey Starlight!
Starlight: What!?
Facing Pinkie made the beam hit her instead of the apple
When the light vanished, Pinkie felt a wierd feeling in her stomach, as if it was contracting
Around her, she saw the entire world expand, Starlight herself looking more like an alicorn than a unicorn, and then some creature that towered above even the largest dragons
Starlight had a worried look on her face
Starlight: Oh dear, this is a real problem!
Pinkie giggled
Pinkie Pie: What do you mean? What's wrong with being tiny?
Starlight levitated Pinkie up to her gargantuan eyes, which were beginning to water up
Starlight: You don't understand! I should never cast spells on my friends! Twilight's gonna give up on me for good this time, I'm sure of it!
Pinkie Pie: Oh pshaww, this isn't as bad as when you hypnotised us. I've still got my free will, haven't I?
Starlight: Yes, but think about how much trouble I'll be in if Twilight sees
Twilight: Sees what?
Hurriedly, Starlight hid Pinkie in her mane
To Pinkie, Starlight's mane no longer looked like a bed of fur, but rather an exotic purple/blue bush
Starlight: Oh uh, I was just, er…remembering where I put my board game collection, back in the Crystal Empire.
Twilight: …What does you being in trouble have to do with board games?
Starlight: Have you ever heard of "TroubleTM", you know the one where the dice is in that little container and you-
Twilight: The Pop-O-Matic?
Starlight: Yeah, yeah!
Starlight was trying her hardest to keep it cool, and she could feel Pinkie Pie getting excited as her hoofsies drilling on her skull like 4 individual lice
Twilight: Oh I'll see if I have it somewhere here. We could play it when you're studying
Twilight started leaving the room
Starlight: Sounds good.
When the coast was clear, Starlight removed Pinkie from her hair
Pinkie Pie: What's so wrong with not telling Twilight about me? She'd be able to unshrink me you know.
Starlight: Well, it only lasts for two minutes, so you'll unshrink in a moment
Oh how naïve Starlight was
Pinkie started shrinking even smaller, down to 1% of her original size
Starlight: Uh oh. Oh, nononono! I forgot to carry the x!
Pinkie was still being levitated, so she didn't notice she had shrunken further down
Pinkie Pie: What!? Don't tell me I've shrunken again!
Twilight's hoofsteps were coming from down the hall
Starlight knew putting Pinkie in her mane again would be uncomfortable, so she had to take more extreme measure
Starlight: Oh, forgive me for this, Pinkie Pie
Pinkie Pie: What are you tal-
Starlight's maw widened as Pinkie was dragged closer by the cyan aura
A tongue the size of a living room carpet was going to be Pinkie's new seat it seemed
That is before Starlight moved her tongue upward and placed Pinkie underneath it
An overwhelming scent of spearmint was exhausting her to the point of dilerium, and it was only going to get worse
Twilight: I've got the game!
Twilight was bringing the board game in
Starlight: Oh uh, I don't need it right know
Every word Starlight uttered
Every movement of her tongue essentially dominated Pinkie's body, drenching her in saliva and breaking her eardrums over again
Twilight: I know, but just in case. Say, you haven't seen Pinkie Pie, have you? I swear she said she's watch over you
Starlight: Oh her, heheh…
Pinkie barely made it out of her pink, fleshy prison and was now making a break for one of Starlight's canines, but stopped dead when-
Starlight: She probably forgot it. I'm starting to learn baking's a big responsibility
Twilight: Excellent! Oh, you're learning so much about friendship
Starlight unconciously gulped, sending Pinkie onto her tongue, each of taste buds making it look like the world's biggest sheet of bubble wrap
Twilight left and Starlight spat Pinkie back out into daylight
Starlight: Next time, could you not move around so much?
Pinkie: Implying there's a next time!
The earth pony was very close to fainting under pressure
Starlight: Look, things aren't gonna get any better, and I'm…Pinkie?
A few seconds ago, Pinkie Pie was resting on the table in a puddle of saliva, but now there was just a tiny pink dot which you could fit 5 of in this o
Inside her mane didn't work, neither her mouth
Where else but…?
Starlight: Dear Celestia Pinkie, I'm so sorry
She turned around presenting her behind to the pink pony
Compared to Pinkie Pie, it was now the size of Canterlot, with a tail coming down from what seemed like the Heavans
Even still, she was beind taken closer and closer to it
Soon she could even see Starlight's marehood
In fact that was her destination!
Pinkie had combined look of shock and fear on her face, which was becoming blushing hard
Starlight's anus in and of itself was the size of Sugarcube Corner, the place Pinkie had lived for most of her life, and her vagina the size of the whole Castle of Friendship
Pinkie Pie was shoved deep into the unicorn's cavernous pussy, certain that this would be her end
Unless,
Oh golly, this would be embarrassing
Pinkie: If I have to get outta here, I need to get hot on her spot. G spot that is.
One slippery slidy trek through her tunnel later, Pinkie found the G spot and started banging at it like crazy
She could hear Starlight beginning to moan, so she knew it was working
Twilight: Starlight, what's wrong?
Starlight: Mind if I got to my room?
Twilight: Sure, you poor thing
Starlight raced to her bedroom, not time for teleportation, her heating honeypot was the only thing on her mind
She got on her bed and started fapping her nethers
Starlight: Darn it Pinkie, if you weren't such a pronkaholic!
Her screams of ecstacy became ever higher and louder, and a wall of femcum eventually washed Pinkie out
But it was too late, Pinkie was already microscopic by the time Starlight recovered and checked her bed
Starlight: Oh my God, I've killed Pinkie!
She hung her head in shame as Twilight came in with some tea
She dropped the tea as soon as she saw her student sitting under a pile of her own fluid
Starlight's face grew red
Starlight: Twilight, I can explain
Twilight: Oh Starlight, this is fantastic! I've wanted a vaginal sample from you since the day you became my student!
Starlight was half dumbfounded and half creeped out
Starlight: You have?
Twilight collected a bit in a tube and started heading out
Twilight: Yeah, it's where a bit of he magic is stored, and you store a lot of magic
Once Twilight had left, Starlight tried her hardest to find Pinkie underneath her vaginal cum
She tried calling her name, rocking the bed back and forth, nothing
Her only hope was that-
Twilight: Starlight Sheridan Glimmer!
That couldn't be good
Starlight headed over to Twilight's lab where she could visually see a pink light shine and Pinkie Pie groaning
She opened the door to see Pinkie lying on a table smothered in Starlight's discharge and an unamused alicorn sitting at a desk
Twilight: The board game isn't the only trouble you like to sink your teeth into
Pinkie Pie: Oh please, don't mention teeth