Devilman: Tanjou-hen

Akira Fudou's ordinary life ends when his childhood friend Ryou Asuka reveals a terrifying truth: demons once ruled the Earth and are beginning to awaken again. Convinced that humanity cannot defeat them with human strength alone, Ryou proposes a desperate plan to fuse a human mind with a demon's power.

At a violent Sabbath meant to draw demons into the open, Akira is possessed by the mighty Amon. Instead of losing himself, his compassion survives the fusion, giving birth to Devilman. With a human heart inside a demonic body, Akira becomes both proof of Ryou's theory and humanity's first weapon against the coming invasion.