Title: Brotherhood
Author: Kristen Sharpe
Date: February 15, 2020
Rating: K
Warnings: None
Continuity: Alternate universe.
Disclaimer:  Ao no Exorcist/Blue Exorcist belongs to Kazue Katou, Shueisha, Aniplex, and various other parties.

"Wow," Rin breathed.

Yukio glanced up in time to see his brother hop lightly onto the railing to their left. Beyond the railing was a sheer drop off the side of True Cross Academy's towering structure. But, Rin ignored it, walking his new, narrow path with familiar easy grace as he twisted his head from side to side to take in the view.

Yukio supposed it was impressive. The school was an enormous, castle-like shape of clashing architecture rising over the skyline like an artificial mountain. Elegant in its details but gaudy as a whole.

It might as well have had Pheles' name all over it.

And, now that he'd been strong-armed into this school and its attendant, secret exorcist classes, he was uncomfortably suspicious that the grinning demon wasn't the biggest threat here. He was still working out who was. The exorcists clearly let Pheles do mostly as he pleased. Either they were weak and ensnared in his web themselves, hoping to use him against an even bigger threat, or they were all of the same ilk.

He honestly wasn't sure which possibility was worse.

"Oi, Yukio." Rin's voice was oddly soft. So odd it yanked him out of his bleak assessments.

He looked up to find Rin staring at him uncertainly, tail twitching nervously. He'd need to remind Rin to hide that. In just the last week, Rin had become nearly solid and visible to everyone, even people who couldn't see demons. They were so used to relying on Rin's invisibility that was going to be difficult for them both.

Rin was talking.

"...just wanted to know..." he was saying. "About us being brothers..."

Pheles' revelation. They were full blood brothers. Fraternal twins born in different dimensions due to their... unique heritage.

"Do you...?" Rin worried his lip with one fang. "Do you mind?"

It was a shock. It had shaken everything he thought he knew. It had (almost) destroyed all his carefully built plans.

But, Rin wasn't asking how Yukio felt about being the son of a demon, about being brought here, only how Yukio felt about him.

"I summoned you, didn't I?" he answered. "To be my brother."

Apparently, that was the right answer because Rin's face broke into a wide smile that touched his eyes and made them brighten with something entirely different from the demonic spark of his power. Then, he sobered.

"What about the rest of it?"

Yukio frowned. "The rest is going to take some planning."

Because demonic heritage or not, grinning trickster or not, Yukio had his own plans, and he didn't intend to abandon them just yet.

Rin hopped down beside him, grin back on his face. "Well, you know you've got me on your side."

He did. And, it brought a small, sincere smile to his own lips.