Two teenaged siblings, having moved to the Alola region from Kalos, set off to complete the famous Island Trials, only for wormholes to appear across the region once again, this time summoning creatures from a mystical world calling themselves ponies
Trapped on the other side of the mirror, Twilight Sparkle has to adapt to a world without magic. Given the circumstances, that is the least of her worries.
It was a simple dynamic. Simple enough that it didn't require any questions, only the unspoken agreement to remain silent. It only required Twilight broken into pieces, so she could never put herself back together again.