Ughhh I’ve been trying to draw these three for months but it never came out the way I wanted it to! I’m glad I’ve finally made a pic of this triad that I actually like.
 
In the Deliriumverse, Rainbow Dash is a gay polyamorous trans man (he/him), Quibble Pants is bisexual, and Prince Blueblood is also gay. Rainbow Dash realized he was transgender about a year after joining the Wonderbolts, at the time he was dating Quibble Pants and that was one of the first ponies he came out to besides the other Mane 6, Quibble Dash was surprised, but supported and loved his boyfriend never the less, so Rainbow Dash began his transition, he’s on testosterone but unfortunately can’t do much about his height, in this au spells that increase your height can have a lot of bad side effects and will definitely weaken your bones (which is NOT good for athletic ponies esp) so most short trans stallions don’t risk it and just stay short ( luckily, Rainbow Dash doesn’t really mind his height or his androgynous appearance, he likes being a twink), Rainbow Dash is one of these ponies, Rainbow Dash also decided to keep his name because it’s androgynous, he likes it, and after all he was already a well known Wonderbot and didn’t want to cause too much confusion and drama.  
About two years into his transition, Rainbow Dash and Prince Blueblood met properly though Twilight, at first they didn’t get along at all, then their relationship slowly developed into a ‘friendemie’ kind of situation, both of them are incredibly argumentative and competitive, and would often hang out when friendship missions or Wonderbolt stuff brought Rainbow to Canterlot, they would mock each other or challenge each other to stupid games and competitions, as their friendship grew Rainbow Dash found himself starting to develop romantic feelings for the snooty prince. At first Rainbow Dash ignored his feelings, mostly because he was still in a happy relationship with Quibble Pants, but eventually Bluebood admitted to Rainbow Dash that he had a crush on him too, and Rainbow found that he didn’t WANT to reject him. Before seeing Blueblood again in any context, Rainbow Dash went straight to Quibble Pants and explained everything, Quib was very distressed and jealous at first, but after a long conversation agreed to try polyamory, it was a little awkward for everyone at first, but eventually Quibble Pants and Blueblood became friends and everything started to feel natural, a few years after that, Rainbow Dash proposed to both of them, and they live together happily in ponyville with their youngest daughter, Stardust. Blueblood and Quibble Pants get along well, but aren’t remotely romantically or sexually interested in each other, they’re purely friends, they sometimes get into weird jealousy fueled prank wars or dumb arguments with each other, but outside that they do a pretty decent job at sharing Rainbow Dash.  
Rainbow Dash is technically a prince now, but doesn’t really do anything royalty related outside making guest appearances at special events with Blueblood, also none of his children are going to inherit any kind of political power.