AR∀GO belongs to Arai Takahiro. I probably should not be playing with his characters anymore after the entire Oz and Robot Unicorn Attack art.

Roleswap AU between Seth and Oz, because prompt.

"What exactly is your intention?"

The words faintly echoed in the limited room, breaking the silence with leftover sounds and syllables. The world was succumbing into destruction outside, they knew: the silence was all the answer they needed to the unvoiced question. Still, it seemed like there were other things in Seth's mind.

"Someone needs to save you from yourself," Oz replied simply, Sluagh Ghairm ready in his hands. Seth looked up to him, unfazed by the winds whipping around him. The teen looked so small, even though Oz levitated just a metre. His armed form was menacing up close, with the armour and weapons strapped onto his limbs, but from here, he was just Seth. He was just an eighteen years old who spent his entire short life as part of the Albion, the Sacred Force. "For God's sake, Miller, do you really think that us humans can ever achieve the ideal?"

Seth's lips curled into a snarl, and Oz could see that he was readying his shotgun. A simple Caisleán would block the bullet, they both knew, but this was a battle of emotions. There would be no need for force. Words hurt enough.

"A fool sees not the same tree that a wise man sees." Blake; how easy.

"We can't care and understand the feelings of every single human on Earth," he said, voice soft. The tempest turned into breeze, into benign wisps. In the unlit room of the museum, things faded. "What if you couldn't be just to everyone? There are billions of people on Earth, Seth, and I know you care. I know you care about them."

Something in his eyes seemed to break.

"You care about them far too much. It's— it's not a bad thing. But you're a good person; don't let them break your heart."

It was such a funny thing to say. Outside, London was falling. He knew that there would be bodies on the street when they leave, he knew he would see more limbs than faces, more blood than water. London hadn't rained, but its streets flooded. They were no martyrs. The Earth would not thrive. How was one supposed to keep oneself together when life tore it apart? He could feel the itch in his chest, but he knew his priority was Arago's safety. He knew the weight on his shoulder was exhaustion.

Seth lowered his head, putting the shotgun back into its place. Tired, Oz let the winds die out completely, knowing that whatever menacing air that put on was unnecessary now. But when his feet touched the ground, Seth looked up. His blue eyes seemed wider, more tired with the dark skin under it.

"And you will still protect Arago?"

Oz nodded. "He's the only one who could wield Brionac. We need him to defeat Patchman."

Seth took one last long glance at him before walking away.

A/N: So yeah.

I didn't switch their personalities, although I did come up with headcanons to explain Oz having Sluagh Ghairm. But that's a story for another day.