Ryo, a young professor returning from research abroad, takes his pure-hearted, crybaby friend Akira to a decadent party, where things turn demonic.

Akira has become a completely different man -- he's stronger and hungrier than ever before. He seeks out Ryo for answers.

Betrayed and exposed, Akira becomes a target. After Miki takes to social media to defend his human soul, she and Miko find themselves under attack.

Confronted by Akira, Ryo reveals the truth about demonkind and himself. Humans, demons and devilmen gather for an ultimate battle for the world.