So...I've spent the past THREE. BUCKING. HOURS. trying to find a story I've read a million times.

It's a twi-dash fiction that is...somewhat mature in the beginning, but turns into a slow-burn romance. Basically, Twi and Dash get very drunk, then Twi uses a spell that ends with her pregnant and dash as the father. The two are ostracized by friends, family, and the local community until the Diarchs reveal that the spell used was NOT causing a slow declination in the unicorn populous. It ends shortly after Twi gives birth.

Does this ring a bell to anyone here, or was I the victim of a fever-dream?

i’ve read the story you’re looking for so it wasn’t a fever dream, i’ll take a look through my library and see if i can find it.

https://fimfetch.net/story/104086/rainbows-in-the-night-sky

found it, Rainbow’s in the night sky. it was taken down at some point but it’s on fimfetch.