Aoi Kurogane knew two things with absolute certainty.
First: he was late.
Second: whatever that sound was behind him, it definitely wanted him dead.
He ran anyway.
Paper lanterns blurred past as his sandals slapped against the stone streets of Katsuro's lower district. Vendors shouted. Someone screamed. A tray of grilled dumplings flew into the air as Aoi barreled through a narrow alley, nearly colliding with a shrine maiden who stared at him as if he'd personally offended the spirits.
"Sorry!" he yelled, not slowing. "Very sorry! So sorry!"
The ground trembled.
Aoi risked a glance over his shoulder and immediately regretted it.
The seal, the stupid, ancient, definitely-not-my-fault seal, was glowing.
Not glowing politely, either. It pulsed with violent blue light, crackled with black flame, and hovered several feet above the ground as if deciding whether to explode or swallow the street whole. Symbols Aoi definitely did not know and absolutely had not meant to touch spiraled wildly around it.
"I barely poked it," Aoi gasped as he turned another corner. "Barely!"
The air crackled.
Lightning arced past his ear and shattered a wooden sign into splinters.
Aoi screamed.
This was not how his day was supposed to go. He was meant to deliver packages, get yelled at by rich people, and maybe steal a leftover bun if luck favored him. Not unleash ancient, world-ending nonsense buried under the city.
He skidded to a stop at the edge of a collapsed stairway, chest heaving, heart trying to claw its way out of his ribs.
"Okay," he muttered to himself. "Okay. Breathe. You are calm. You are very calm. Nothing bad is happening."
The seal answered by detonating behind him.
Blue lightning slammed into his back.
Pain exploded through his body, white-hot and merciless, hurling him forward. Aoi hit the ground hard, rolling, dirt and ash coating his clothes. His vision swam. His ears rang.
For a long, terrifying moment, he didn't move.
Then something inside him moved instead.
Power surged through his veins, wrong, ancient, and far too big to belong to someone like him. Black flame coiled around his trembling hands, edged with blue sparks that bit into the air like fangs.
Aoi stared at his fingers.
They were glowing.
"Oh no," he whispered. "No, no, no, this is bad. This is very bad."
A voice stirred in the back of his mind. Not loud. Not angry.
Amused.
So, it murmured calmly, you're the one who broke the seal.
Aoi swallowed hard.
"…I can explain."
The power pulsed in response.
Somewhere in the city, alarms began to ring.
And far above the lower district, forces far more dangerous than Aoi Kurogane turned their attention toward a boy who had never wanted power and had just become impossible to ignore.