Assassin from Abyss

In a twisted universe where demons and devils wage endless war, and every breath carries corruption and malice, survival is the only law. After transmigrating into this brutal world, Kei—a former Yakuza—is reborn as a humanoid beast and thrown into a web of conspiracies, bloodshed, and power struggles. To stay alive, he embraces the darkness within, using his criminal instincts, past-life experience, and growing domain abilities to outsmart and destroy anyone who stands in his way. His greatest ally is Epoch, an artificial intelligence implanted in his mind. But it's also his greatest threat. *"If you fail to evolve... I'll take your brain, your body, and erase your existence forever."* Kei isn't a hero, and he isn't a villain. He's a survivor. If saving lives keeps him alive, he'll become a hero. If cruelty is the only path forward, he'll become the monster everyone fears. In a world where only the strong endure, he'll do whatever it takes to reach the top.