The week seemed to fly in with Sunset being anxious and excited to finally return to Equestria after so long. She could've gone back any time she wanted but she never had a real reason to until now and bringing her girlfriend along would make the trip even better.
They had prepared small bags with a few things like scarves and hats that they may need on the other side, but otherwise had nothing else to stop them. As they approached the portal Twilight stopped.
"Wait Sunset."
"What's up Twi?"
"I just need a minute, I mean I'm about to go through an interdimensional portal to a world of ponies where I myself will become a pony! I'm kind of freaking out a little."
Sunset silenced her with a kiss. "Easy Twilight, it'll be alright, I'll be here the whole time. Don't worry about a thing."
Twilight took a deep breath and clasped Sunset's hand as the two walked through the portal and arrived in a room familliar to Sunset. The blue crystalline walls and purple carpet told her all she needed to know, this was Princess Twilight's castle. And there to greet them was the Princess herself.
"Sunset! It's so great to see you again."
Her eyes quickly darted over to see a mirror image of herself though lacking wings and with distinct black glasses, on her hind legs about to fall over. Sunset and Princess Twilight caught her and helped her onto all fours.
Sunset chuckled. "Don't worry it took me a while to get used to being on all fours again after spending so long in our world the last time I came here."
Twilight blushed but regained her composure.
"Nice to see you again Princess, I fear that people seeing a mirror image of you as a unicorn might confuse them but other than that I'm more than happy to be here."
Princess Twilight smiled "I actually already thought of that. Could you hold still for a moment?"
Twilight then felt herself get enveloped by magic and suddenly her coat darkened into a deep dark violet color, her mane and tail shifted to contain more pink than blue with darker purple streaks and at a glance, she didn't look too different to the demon that haunted her nightmares for years. A glance at herself in the mirror made her recoil in shock.
"Ahh! I look like...like...no, please no." She then fainted.
Princess Twilight was confused. "Why did she faint? All i did was change her appearance a little."
Sunset knew the problem. "Twilight I know it wasn't intentional, but you made her look like Midnight Sparkle, the demon form that she took when the Equestrian magic corrupted her at the friendship games years ago. Even now she still has an occasional nightmare about it."
"I had no idea, I'm so sorry."
The unconscious unicorn stirred and was helped up by Princess Twilight.
"I'm so sorry, I didn't know."
"No It's fine. I Actually kinda like the c-color." She said through gritted teeth.
"I can change you to a different color if it would be any better. I know now that this reminds you of that day. I may not have been there but I heard what happened, from Sunset and from you. You are not that monster anymore, and as long as you have Sunset you never will be."
"Thank you, but I'm fine like this. In fact if i'm going to make an attempt to finally overcome my fear. Call me by her name. While I'm here, I shall be known as Midnight."
Sunset gasped. "Are you sure honey?"
"Positive Sunset, I need to get over my fears and this could be a good chance. If I get used to her colors on my body, then perhaps I can finally move on and realize that while she is part of me, she won't overtake me again."
Sunset smiled at her and nuzzled her. "Well then Midnight, shall we take a walk into town? I want to show you my world."
Twilight smiled as the two made their way out of the castle.
All through the town was blanketed by a light fall of snow. Midnight recognized many of the ponies in the town as there were people in her world who looked just like them. Most of them however were fully grown and working jobs or even owning their own businesses. She found it hard to believe that the two girls who became CHS' first openly gay couple could have pony counterparts running a sweet shop, and yet here was Lyra and Bon Bon. Or that in Equestria Vinyl had ended up with Octavia after all and the two shared a home where they produced music together. She also met the pony counterparts of all her friends who of course knew she wasn't their Twilight, but treated her as a friend all the same.
The whole time through the town however Midnight noticed Sunset wouldn't take her eyes off the building of Ponyville and all the ponies in the streets. She barely took a second to even look at Midnight.
Sugarcube Corner was packed with a line that stretched out the door so they decided instead to visit Bon Bon's sweet shop to get a bite to eat. The two hoped she would have something warm as they were freezing cold from being outside all day.
"Hello, I'm Bon Bon. What can I get for you?"
Sunset shivered as she spoke "You g-got anything warm?"
Bon Bon thought for a minute. "Well usually I don't like to go into my personal stores for customers but I do live above the shop. Would you like some Hot Cocoa?"
Midnight smiled at her "We would love s-some thank you."
Sunset had the forethought to bring some bits with her but Bon Bon refused them.
"But why? We're customers, don't you want us to pay?"
"It's cold out, the least I could do is let you warm up with some of my cocoa, and you two remind me of myself and Lyra, you're cute together. You are together right? I don't want to assume anything."
Midnight giggled "Well thanks, and yes we are together." She confirmed as much by kissing Sunset's muzzle.
Bon Bon smiled. "If you really want to be paying customers I've got some nice fresh chocolates just made this morning that you could buy."
Sunset placed some bits on the counter "We'll take them thank you."
After saying goodbye to Bon Bon they made their way back to the castle and spent the rest of the day chatting with Princess Twilight and staying warm by the library's fire. Hearth's Warming Eve was tomorrow night and Twilight informed them her family and friends would be arriving tomorrow morning. Midnight and Sunset were shown their room together. But as they lay in bed Sunset asleep within moments, Midnight lay awake thinking.
She noticed Sunset being almost overly friendly towards the Princess, accepting nuzzles and hugs, nuzzling back more than once. Maybe it was a common form of affection here but she didn't know that, she could swear Sunset was inches away from kissing Princess Twilight's cheek at one point too. Suddenly a voice within her spoke up from the darkness.
"Don't you see, she clearly cares more for that pony than she ever did for you. She only stayed with you because she felt guilty about leaving Equestria and wanted to stay in your world, and you were the closest thing to the Princess that she could have. She doesn't care for you and never has, you were just a proxy for the real girl she loved."
Midnight grew angrier with every thought, no matter how hard she tried to reason otherwise, this voice kept telling her Sunset never loved her in the first place. Was it right? How could she know. She was tired and decided to sleep and deal with it in the morning.