Twilight's an Alicorn, a race that is known to have a lifespan that borderlines eternity. Lucky for her, there's another species that lasts just as long as she does.
I mean, I could ask Twilight out. I know she would say yes, and we would both be oh so happy, but...it's scary. I think we're in a good place right now, right? We both know our feelings and there isn't a reason to rush on them. Right? Oh, Fluttershy,
When Luna's teachings on entering dreams ends up revealing Fluttershy's crush on Twilight, Twilight had no idea how to respond; she even suspects the feelings are mutual. So one thing leads to another, and the two share a simple dance.
Fluttershy grieves over the loss of one of her dearest friends and pushes those closest to her away. But one pony is more persistent than the rest... TwiShy
Fluttershy has had a crush on Twilight for awhile now, obvious to the signs that one another likes the other back, she and twilight keep there feelings to themsleves. Until, a slumber party game of truth or dare that is.