Seb's birthmarks were different, particularly the one wrapping around his wrist. Instead of black, red shifted into yellow into green into blue before fading back into red.

(There's a writing game/challenge on tumblr where we write an AU [alternate reality/universe] story every week. I'm going to be writing a multi-part story about all five of my main characters using the prompt “A [platonic] soulmate AU where you have a black stain where your soulmate is supposed to touch you for the first time and it turns to millions of colors once they do.” The events are all [or mostly] canon to the series; the only real change are the soul-marks. This chapter of Etri's would take place about seven years before the trilogy.)

Unexpected Inspiration AU Series: "Stuck With You"
Chapter 2
(First Chapter, Previous Chapter, Next Chapter)

The crisp snow crunched under Etri’s feet in a sickening way reminiscent of the rough gravel floor of the Sanctuary's acolyte quarter. His skin burned every time he sunk into a knee-high drift, the pain a constant reminder of the flames that waited for him should they be caught. His fingers were numb under thin gloves meant for concealment, not warmth, and his robe was nigh-useless outside the cavern city. It had been cold underground-- every day of his life had been spent shivering-- but nothing had prepared him for this overwhelming numbness spreading through his body. If he couldn't find shelter soon, it wouldn’t matter that they had escaped. They would die anyway.

There was no shelter on this gods forsaken mountain. What appeared to be a city from a distance had turned out to be nothing but a dilapidated pile of stone. Once people had lived here; whether they were the priests and priestesses who were banished underground long ago or if they had merely been victims of the cold, he could not guess. All that mattered was that they were no longer here. Ghosts, while a possibility for information if he could get them to listen, were to be avoided in case they were eyes and ears to those who lived below.

There would be no help for him and Seb here.

At least the snow had stopped, which meant they could move again without fear of walking in circles. Etri had no way of discerning direction without the tunnel markings of which he was familiar, but a clear sky and a visible landscape made for a better chance at getting away. Until last night he had heard only stories of the sky and these had not prepared him for how incredible a dome-that-was-no-ceiling could be. Only the most powerful were allowed to ascend the mile-long temple stair and he now understood why. Given the sight of so many stars, of so much space, what acolyte would wish to remain in the gloom and murk? True stars were beautiful sparks against a blue-black expanse far greater than the largest cavern, so extraordinarily unlike the sickly luminescent moss lining the walls throughout the city or the flickering caged magic the light-summoners used to illuminate the Sanctuaries.

At this moment the snow rolled on forever, bright and blinding in the sunlight. It was painful, disorienting, and not as pleasant as night, yet still superior to the confining stone that had been Etri's whole world only hours ago. A part of him feared that this whiteness and brilliant light meant he and Seb were dead and within the realm of the god of light. Perhaps in sacrificing his future to save his kin, Etri's own god had forsaken him and left him in this cold, bright place empty of all life. It made far more sense than the fact that they had not been followed; only his own footprints marred the fresh snow and he could not sense any shadow nearby. If leaving was an automatic death sentence, where were the ones who would inflict this punishment?

Etri retraced his steps to where he had left Seb in the only shelter he could find. It had no roof, but two and a half walls had prevented much snow from drifting inside. When he stepped out of the snow and into mud and unexpected warmth, he stopped to stare. Seb sat with his head bowed and his arms wrapped around his knees inside an expanding circle of slush. Within moments this melted, turning the ground to mud before it dried so solidly the earth split and cracked. How had Seb kept magic this powerful a secret for so long?

That was when Etri noticed what was most certainly not hidden. He sidled up to his brother without actually looking at him. "Seb?"

Seb sniffled. His voice was so quiet, so defeated, that Etri strained to hear it. "Don’t wanna be called that anymore. They named me that."

This choice was understandable, all things considered. What was not understandable was the fact that whatever-he-wanted-to-be-called was no longer wearing anything. Etri fumbled around for the discarded robe and held it out to him, taking care to only look at Seb's face. As a temple servant, Seb had been allowed to show this, although Etri and the other acolytes were forced to wear deep hoods.

Seb snatched the robe only to toss it away with a grimace distorting the features Etri so recently learned matched his own. "No! Those clothes are bad! Everything there is bad! I’m not gonna-"

That was all Seb managed to get out before his body begun to shake. Etri jumped to his feet, ready to stand between him and the shadows that must be causing him harm-- until he realized Seb was simply sobbing. Although if he was caught crying... no, that was the wrong thought. If he was discovered to be crying, that would mean they were caught and showing emotion would be the least of their crimes.

Etri had learned no words for comfort or compassion, even for the one person who meant everything to him. He could only watch as Seb sunk to the scorched dirt in tears. As the resuming snowflakes hit his too-warm skin, some melted over the black stains scattered along his spindly limbs. When Seb shifted to wrap his left arm behind his neck as though trying to retreat into himself, Etri's assumption about the two of them being identical was proved wrong. Seb's birthmarks were different, particularly the one wrapping around his wrist. Instead of black, red shifted into yellow into green into blue before fading back into red. Once when he was still regarded as a servant, Etri had been sent to the Sanctuary of Light to deliver a message. There he had stared in awe at a crystal that reflected light into a multitude of colors yet had no color itself. Could Seb have a similar phenomenon on his body because he possessed light magic?

Seb's sobs intensified and Etri ached for a way to help. He could not change what had happened and could not bring back what was lost, but perhaps he could influence the future. He now knew that he would not survive without Seb's warmth and in this state Seb could not take care of himself. Should they be caught, their individual magics would likely protect the other. If they were to live, it must be together. If they were to have a future, they must abandon their past. Etri took a deep breath. He had already failed the rules against touch by grabbing Seb's wrist to pull him away from fire and death and into the relative safety of the snow. He would willingly fail over and over if it meant comforting the only person who mattered.

Decision made, he tugged off his gloves only to stop short of reaching for his brother. Colors swirled and morphed over the palm and fingers of one hand in a perfect mirror to the mark on Seb's wrist, although part of the birthmark remained as black as the one on his opposite hand. This was strange, but ultimately unimportant. Etri dropped the hated gloves onto the dirt and rested his hand lightly on Seb's shoulder. He would stick by Seb-- or whatever he chose to be called-- from now on. They would get through this together or not at all.