Ch81. Pain as a teacher (5) - [Clue]

Shinji's body convulsed as something unseen ripped through him. It was not physical – not entirely, at least – but it was real.

The sensation of a thousand invisible hooks sinking into his flesh, pulling at the marrow of his bones, at the very essence of what he was. He wanted to scream, but his voice had been stolen, held captive in his throat.

The entity before him shifted, its amorphous head tilting, watching. Its countless eyes blinked in eerie unison, each one digging into him, stripping him layer by layer.

"Power has a price." The voice whispered, but now it was inside his head, pressing against the walls of his skull.

The blood he had offered was no longer his own. It had become something else. The tendrils of darkness that had emerged from the abyssal creature drank it, fed on it, transformed it. The sigils on the altar pulsed faster, their glow intensifying until they were no longer red, but black, a void in the shape of light.