Possible fanfiction scenario:
Nyx's birthday is coming up. She should be excited, she should be happy. Instead, she's feeling melancholic.
How can she really celebrate a birth-day if she wasn't really born the normal way?
To help Nyx, it might take somepony's unique perspective on the subject…
_
"Hello there!"
"OH MY GOSH! You're like a Crystal Pony, but filled with cola!"
"Well, I -""
"But Crystal Ponies only look see-through because of how their crystal magic bends light, I think, but you're actually see-through!"
"But you don't have internal organs, how do you eat food?"
"Hmm, you see -
"And your coat is… glass? Plastic?"
"It's —"
"What happens if you stub your hoof, does it crack? Wait, if it's plastic, then does it bend inwards?"
"Is it bad if you run out of cola? What, if the cola goes bad? Do you need to, like, change it for new cola regularly or…"
"AHAHAHAHAH! Oh wow, you sure are Twilight's daughter alright!"
(I hope her 'experiments' aren't as bad as her mom's.)
_
(A few months ago)
_
"Welcome to Ponyville, new pony who is also a walking, talking cola bottle!"
"Haha, I sure am!"
"Here's your own very special welcome-to-Ponyville-party invitation!"
"A party? For me? Oh wow, that's —"
"YOU…"
"Hmm?"
"Oh no."
"You. Can't. Exist."
"You… are not scientifically possible."
"I, uh…"
"I MUST STUDY YOU."
"RUN!"