Upon finishing her story, Twilight was smiling again. "After that," she said, "we started dating. It was a little tough since it was long-distance, but Cadence helped a lot. She kept finding any excuse to send you on trips to Ponyville. I remember one time she had you come to town to help me pick out a new high chair for Flurry Heart because she outgrew the old one I'd bought her."
"Well, I do take my responsibilities as Flurry's crystaller pretty seriously, so Cadence is often willing to ask for help with things that other ponies might find strange," Sunburst said. "But yeah, it seems like she probably had ulterior motives in that case."
"Maybe you really thought it was for Flurry at first, but it became pretty obvious to both of us what her true motives were," Twilight said. "Has your Cadence ever sent you on official crystaller business as a way of encouraging you to get a marefriend?"
"Not that I'm aware of," said Sunburst, tapping at his goatee. "However, I might have to think back on some things. Like, there were a couple of weeks there where she insisted I go buy Flurry something new every day from this one particular toy shop run by a mare about my age. And then she invited that mare to some royal functions to perform 'on-site quality assurance' and told me to work with her on checking Flurry's toys. At the time, I thought she was being an overprotective parent, but now..."
Twilight nodded. "Yeah, that sounds like my sister-in-law. If she thinks she sees the possibility of a connection between two ponies, she'll go out of her way to make something happen. Apparently that trait crosses universes, too."
After having been silent for a while, Starlight joined back in the conversation. "Gosh, how crazy is this? Alternate universes. Alternate versions of ourselves. Similar, and yet still distinct."
Before Sunburst could say something in response, his stomach gave a low rumble. "Oh," he said, looking down at his torso. "I guess one of the differences is that this version of myself hasn't eaten in a while."
"We were both waiting so we didn't spoil our appetite for the planning dinner," said Twilight, standing up and moving into the aisle of the train car. "I'm actually feeling a little peckish myself. I'll go to the snack car and get us something to eat. Do you want anything, Starlight?"
"I'm good, actually, but thanks," said Starlight.
At that, Twilight was gone in a flash of teleportation. This left Sunburst and Starlight alone and the two looked at each other for a few moments. Again, Sunburst tried to gauge Starlight's expression to judge how to proceed and, again, he found it to be basically impenetrable. Her forehead was wrinkled. Her brows were raised, Her lips were pursed in a soft frown. And she still seemed more interested in looking at his suit than his eyes. Sunburst didn't know what to make of it all.
Before he could say something, Starlight spoke first. "So when you became pen pals with Twilight, you really weren't trying to start anything romantic?"
It took Sunburst a moment to think of how he wanted to phrase his response. He understood what she was asking, but he didn't understand why she was asking him about something like that. He certainly didn't have any insight into what his other self might've wanted from being pen pals.
"I mean, I can't speak to what your Sunburst was thinking. Maybe romantic interest was his reasoning all along or maybe he only decided to take a shot at Twilight after a few letters. Obviously, he and I differ somewhere in between that trip to Ponyville and his letter asking Twilight to the Northern Lights Festival. For me, personally, romance was never part of the equation. I thought it was nice to have a friend to talk to about history and stuff. Nopony else ever cares about arcane magic and Olde Ponish."
"Oh, okay." Starlight looked out the window. The train had made it past Canterlot and was now heading northwest across the plains beneath Cloudsdale. Outside, the rainbows gently falling from the clouds gave a nice splash of color to a scene that would've been otherwise rather dull. Instead, it was one of the best vistas on the ride between Ponyville and the Empire. In spite of that, Sunburst was fairly certain that Starlight wasn't admiring the view.
"Is everything alright?" he asked.
Starlight kept looking at the rainbows, but asked, "In your universe, if you aren't with Twilight or some toy shop owner, who did you end up with?"
Once more, Sunburst had the suspicion that he shouldn't just blurt out his answer. He decided to take a page out of one of the political lessons Shining had given him on how to talk to the press. "I'm really happy with what my life in the Empire has given me. I have a respected position that also gives me time for my academic pursuits. What more could a pony want?"
"What?" Starlight brought her eyes back to Sunburst. "Are you telling me you aren't even dating anypony?"
Not able to think of another way to give a diplomatic response, Sunburst simply said, "Pretty much. My mom set me up on a blind date about a year ago and I don't think I've been on a date since."
"But why?!" Starlight's expression had changed somewhat. Her eyes had widened and her mouth showed some of her teeth. Irritation now tinged the words she spoke. "You have everything going for you. You said it yourself: you have a respected position that gives you plenty of free time. Your patron is literally the Princess of Love! You're smart and interesting. You helped save the Crystal Empire when the Heart shattered and then you helped save all of Equestria from the Pony of Shadows. In this universe, you're getting ready to marry a Princess. In yours, you could easily get any mare to go for coffee with you, at least."
"I'm more of a tea stallion, personally," said Sunburst, smiling a bit.
However, Starlight's mood didn't lighten at the joke. "You know what I'm saying. Why don't you have a marefriend?"
Sunburst was perplexed at the gravity behind Starlight's question. This did not seem like simple "mare talk" about romance. Starlight sounded exasperated. Her words weren't gently probing for insight. They were clawing at his chest in an effort to excavate his heart. As the muscles in his torso tightened, Sunburst couldn't help but feel a bit defensive.
"Why do I need one? I mean, I have nothing against getting a marefriend, but I'm not in any rush to find somepony and start a life together. I really am happy being a researcher and Flurry's crystaller. Plus, relationships are a lot of work.
"There was a time a couple years ago when it looked like my life wasn't going anywhere, but now I'm getting my life on track and I don't want to complicate things. I know for my mom—and I guess Cadence, too—me ending up with somepony might seem really urgent. To me, it just isn't."
"But once things stabilize," Starlight said, "you're gonna start trying to pursue a relationship, right?"
Where is this coming from? In his universe, Starlight and Sunburst never talked about such things. Therefore, he couldn't tell if this was unusual behavior. Starlight could certainly be intense when she wanted something, but Sunburst had no idea what she wanted from him.
"I hadn't really thought about it, to tell you the truth. Maybe I'll find somepony, maybe I won't. It really isn't a priority for me."
"Alright, whatever." Starlight went back to looking out the window. She framed herself so that her back was firmly facing Sunburst and her shoulders sank with a huff.
Bafflement returned to Sunburst's face. He never felt particularly comfortable interacting with other ponies. He preferred his solitude and the company of books written by those who'd been dead for centuries, but today he really seemed to be striking out over and over again. He let out a sigh.
In a magenta flash, Twilight suddenly appeared between the two. She had a couple bags of goodies in her magic and a smile across her muzzle. She turned to Sunburst, presenting him a brown paper bag. "I've got some good news from the snack car: they had lemon cinnamon rolls!"
Sunburst immediately brightened. "What? That's crazy! No place ever has those." He happily snagged the bag from Twilight. When it was near his muzzle, he could smell the spicy aroma through the paper. "How did you know lemon cinnamon rolls are my favorite food?"
Before Twilight could answer, Starlight piped up from her window with, "How do you think?"
It took a second, but Sunburst quickly realized that his question was indeed superfluous. He was going to have to get used to the idea that the Twilight in this universe probably knew a lot more about him than most ponies. In fact, she might know more about me than anypony in my universe too...
"We'll call it an educated guess," said Twilight, sitting down next to Sunburst again. "Besides, even if your favorite food was something else, I could always blink back over to the snack car."
Sunburst thanked Twilight. He began to open the packaging, but then a thought occurred to him. "You know," he said, "in my universe, you teleport all the time. Blinking in and out of places with magic is like a thing with you. Doesn't it bug you that the other me is holding you back?"
"Please, don't think like that," Twilight said, scooching closer to Sunburst so that their shoulders touched and their muzzles were only a hoof-width apart. "I've told you before that you never hold me back. You push me to be the best pony I can be."
"Uh, we only just met," Sunburst said, moving a bit away from the Princess. "I think you mean that your Sunburst pushes you to be the best pony you can be."
"Of course!" said Twilight, blushing. "Yes, I mean the other you does that. My Sunburst pushes me." Twilight also moved herself so that she was facing forward again instead of looking right at Sunburst. "I'm sorry. I'm still a bit confused is all. It's just, you're so much like Sunny."
Sunburst nodded. "I understand. Anypony would be confused and stressed out if she were you. It's not every day the pony you love goes missing into another reality."
"Not gonna lie," said Starlight, turning back to the pair. "I was actually worried Sunburst might disappear before the wedding. However, I was thinking nerves and cold hooves, not universe hopping."
Sunburst raised an eyebrow at the lack of tact and Twilight let out a whimper.
Realizing what she'd just said to Twilight, Starlight quickly moved to rectify her mistake. She got out of her seat and came over to the pair, putting a forelimb around the Princess' shoulder. "But we'll get through this! Don't worry, Twilight. Us three are gonna figure this out. You'll be saying your 'I dos' with Sunburst at the altar in no time flat... Or, you know, at the scheduled time you'd planned on."