I’m afraid it predates me a bit, but the way I got into it started with a navigational pegasi, a botanist unicorn, and, eventually, sisters.
sorryi love drawing bloody things
I think it’s a rule that you can’t draw one without the other or something.
I don’t make a habit of shipping ponies, but as far as I’m concerned, these two are canon, after seeing them duet on Rainbow Rocks.
Fairly certain even the best of friends don’t look at each other like this.