Work Text:
It had been a long time since Hyojin had last seen his key change. He watched as it flickered and shifted between his fingers, as the teeth of the bit became ragged and its bow melded into a simple ring. Sometimes the keys became prettily crafted, delicate and silver with admirable metalwork. Other times they were rusty, their stems stubby or stocky. But each time his key changed, it seemed to mean that Fate required him somewhere new, and he let himself follow her lead.
The quickest way to travel through the hour, for Hyojin at least, was by train. It was the easiest way to go undetected by the people of the time, seeing as he had never bothered to go farther back than the invention of the railroad. Of course, traveling so frequently made keeping track of personal anniversaries a little... difficult.
His body was young, at least, so he would continue to take the train.
Wherever he went, however, he was met with the same individual. With his first few trips, Hyojin believed it was simply coincidence; just a family line with children who all held such a likeness to each other that their sons were recognizable no matter the period. The next few trips, however, he started paying attention.
The man had never interacted with him, yet he was always present. (The one exception being the Ruins, but nobody was there save for a lonely guard.) Hyojin started taking his rides at different times of day, just to see if that altered anything, yet the man was still there. No matter the timeline, or the location, there was always a way for him to exist.
The first time they truly met had been an accident. Hyojin had stood on the platform of a train station in Moscow, thinking deeply about revisiting somewhere. It hadn't meant to be a jump, just a little manipulation of space, but he had ended up in an empty carriage with space warping around it at speeds he had never seen before.
"You!" he realized, looking at that familiar man, who was looking right back at him. He leaned nonchalantly against a table, a strange drink clasped loosely between his fingers. It gave off a strange glow, reflecting cyan in the man's eyes.
"Me," he agreed with a smile. "You're an interesting mortal, if I'm allowed to say."
"Mortal?"
Hyojin's head was still spinning from the jump, and as he caught his reflection in the windows of the cabin he realized his hair was flickering between his favorite orange-red and the black with white that usually accompanied him in Europe. He was well aware of his own mortality, even as he bent time around his existence, but to have a stranger address him as such as a greeting truly struck him as strange.
The man's hair was flickering too, but less sporadically than Hyojin's. It was as if half a minute passed before he was looking at the same face but a different style; first pink, then choppy white, then a neat brown before it cycled around again. But time was different on the trains, so Hyojin couldn't be sure.
"You're mortal, no?" the man said amusedly. "Though you have interesting abilities."
"Does that make you... not? Mortal?"
"I believe the word is immortal, yes," he smirked, and Hyojin rolled his eyes.
"Are you some kind of god, then?"
"Not at all. Just someone who cannot die."
"So when I've been seeing you wherever I jump-"
"That's me, yes." His eyes glittered with mirth. "Yuto, by the way."
"Hyojin," Hyojin returned.
For a while, it became a game. Who could find the other first, which of them knew the most about the period, or the area, or the culture. Hyojin would step off his platform and meet eyes with that familiar smile, and they would play cat and mouse through the cities and landscapes until they grew bored.
Until one day Hyojin jumped, and the timeline fractured.
"Fascinating," Yuto commented beside him.
"You knew this was coming, didn't you?" Hyojin accused.
"It was only a matter of time," Yuto said solemnly. Then he began to shriek as Hyojin battered him with his fists for his terrible joke.
"I despise you," he grumbled.
"You don't," Yuto laughed, and together they stepped onto the fragile line, following it to where it had shattered.
A laboratory.
("Where most problems are caused," Hyojin sighed. Yuto shot him a look of levity.)