Fluttershy: “Discord don’t be so frowny, this is a special moment with Zephyr and Tree Hugger!” She exclaimed with excitement, though it was about as loud as a pencil dropping, given her naturally quiet voice. “ And why did you change your appearance to a pony?” She gave a gentle smile with a tilt of her head so show obvious curiosity.
 
Discord: “My dear, we are in a mud puddle in the middle of a forest. How special can this be?” Discord grunted, his frown dropping more. “And I am like this because I refuse to have my beautiful reputation tarnished by being near these…..whatever they are!”
 
Fluttershy: “My brother and friend.” Fluttershy answered. “This is a special ceremony to unit two ponies who love each other! Like how our wedding was, didn’t you think that was special?”
 
Discord: “You know I do! But this….with these ponies…I just don’t understand it and I am the Spirit of Chaos and Disharmony!”
 
Tree: “Real-ly? Righteous! I wondered why your chakra seemed so out of flow with the cosmo’s gentle harmonized current.” Tree Hugger cheered in an almost too slow kind of manner.
 
Discord: “WHAT!? YOU ALREADY KNOW THAT! THIS IS WHAT, OUR TENTH TIME MEETING!?” Discord shouted very animatedly before giving up on the conversation completely. This pony would never really remember it anyway, considering the many times he had been introduced to her.
 
Fluttershy poked Discord’s nose, leaving a smudge of mud there, making Discord jump with surprise before pouting again.
 
Fluttershy: “Be kind, Discord. It won’t take too long and we can do whatever you want after.”
 
Discord: “Anything?” He gave a suggestive smile. Fluttershy glared up at him.
 
Fluttershy: “You are not sending my brother and Tree Hugger to another dimension like you did at the gala!” She lectured.
 
Discord: “You said anything!” Discord crossed his hooves together, letting out a huff of frustration. “And it was going to be a very nice dimension, just so you know! Only a few pony-eating flowers and such! They love flowers!” He gave an exaggerated sigh, before speaking again in a monotone voice. “How long will this be anyway?”
 
Tree: “The ceremony starts after we have coated ourselves with our mother earth’s natural life giver, then move forward into our goddess’s light till we are cocooned into our old casing then freed and reborn, where we will then combine our loves’ unity till we are together as one.
 
Discord:………………. “WHAT!? WHAT ARE YOU EVEN SAYING! NONE OF THAT MADE ANY SENSE IN THE LEAST BIT!”
 
Zephyr: “Calm your tone my Chaotic in-law, else you’re gonna throw everyponies peace off. This is supposed ta’ be a stress free moment of union! What my little tree bug is tryin’ ta say is we cover ourselves in mud, go to the sun and let it dry till it all hardens and breaks off of it’s own accord, then freeing us and giving us a new rebirth of ourselves!” Zephyr exclaimed, waving his arms and spreading his wings out more than what actually seemed necessary when talking. “Then we have our own ‘unity’ with our lovers under the light of day! You with your lady and me with mine, if you know what I mean.” He gave a hinting look as he put his hoof around Tree Hugger.
 
Discord: “Why Thank you, Ziffy, Zig-Zag, or whatever your name is, but that still - ! …..Ohhh…..” Discord stopped speaking when he finally understood the meaning of ‘unity with a lover’. He glanced at Flutterhy, who had a look of confusion.
 
Well….he might as well tell her. She made him come all the way out here to sit in mud after all.
 
Discord leaned close to Fluttershy’s ear for only her to hear, then he told her what it had meant. Fluttershy’s face went from a cute curious expression to a look of horrific embarrassment with a nice shade of red to follow. Discord couldn’t help but smile at her reaction. This meant they could leave!
 
Discord: “Thank you for the wonderful….mud…and all, but Fluttershy and I really must be off. Mirage’s foalsitter is a rabbit after all and frankly I don’t care for the dust bunny. Have fun in your mud bath! Come dearest Fluttershy!” Discord cheered, excited to get away from these crazy weirdo.
 
Fluttershy was still in a state of shock, so Discord picked her up by the scruff of her neck with his mouth and happily pranced out of there.
 
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Zephyr and Tree Hugger don’t really get the whole public displays of affection thing, poor Fluttershy! But, it is supposed to be a special ceremony and they wanted others to be there!
 
So, I don’t really see Zephyr Breeze and Tree Hugger being the ‘married’ type. So, instead of a wedding (They won’t let a ring or papers tie them down!) they do this type of ceremony where they literally (in some sense) reborn themselves and use their ‘new self’ to dedicate themselves to each other as each other’s main one and only. They do have an open relationship with other ponies, but they always come back to each other by the end of the day.