Devilman: Tanjou-hen

Akira Fudou leads the life of a typical high school student. After a chance encounter with school bullies, he is rescued by his childhood friend Ryou Asuka. Ryou and Akira catch up over the course of an afternoon that ends with them crashing a party at a nightclub. Initially uncomfortable with the environment, Akira is shocked when violence provokes some of the club's partygoers to transform into demonic monsters. He and Ryou are only saved from the encounter thanks to the intervention of a great demon known as Amon. Amon possesses Akira, and the two together form the powerful Devilman⁠—a being that, due to the influence of Akira's strong empathy for his fellow man, is resolved to keep the human race safe from the threats of demonkind. Akira is just another normal kid in modern-day Tokyo, until an old friend of his, Ryo, shows up and turns his world upside down. Akira learns that there is an upcoming war of demons on humanity and he has just been enlisted for a major tour of duty. But the only way to fight a demon is with their power, so Akira and Ryo risk a dangerous ceremony in an attempt to create humanity's only hope — the powerful Devilman.