"Lomien Man" is a science fiction anime series set in a dystopian future where humanity is on the brink of extinction due to the emergence of biomechanical creatures known as "Lomiens." These creatures, born from a mysterious energy source called the "Lomien Core," have overrun the planet, forcing survivors to live in fortified cities. The story centers on a young engineer named Kael Ardent, who discovers a prototype exosuit capable of harnessing the Lomien Core's energy. This suit, known as the "Lomien Man," grants its wearer immense power but at the cost of gradually merging the user's consciousness with the Lomien energy, risking loss of humanity.

Kael is thrust into a conflict between the remnants of human civilization and the Lomiens after his city is attacked. Alongside a group of survivors, including a rogue scientist named Dr. Elara Voss and a former soldier named Ryn Jax, Kael must navigate the dangers of the wasteland while uncovering the truth behind the Lomien Core's origin. The narrative explores themes of survival, sacrifice, and the ethical implications of wielding power that blurs the line between human and machine. As Kael battles increasingly powerful Lomiens, he struggles to maintain his humanity, questioning whether the suit is a tool for salvation or a path to becoming the very enemy he fights. The series balances intense action sequences with introspective moments, delving into the psychological toll of Kael's transformation and the moral dilemmas faced by those fighting for survival.