After being defeated by the Holy Hero at the peak of his power, **Kaiser von Zerath**, the legendary Demon King known as the greatest threat to the fantasy world, awakens once again—this time in the body of a baby: **his own young son**.

Retaining all his past memories, Kaiser realizes how futile his former ambitions of conquest truly were, and he resolves to change. Determined to live a new life as an ordinary child, he sets out to learn manners, ethics, and even how to be a good parent—to himself.

Unfortunately, the world is not so quick to forget the past. Hero parties, kings, and even demonic creatures begin to suspect that this mysterious infant may be a new looming threat.

> Can a former legendary villain truly change? Or will fate keep pulling him back into the darkness?

Wooden ceiling. The smell of warm milk. And a soft voice of a woman whispering gently, "Sweetheart… are you awake?"


I tried to move my body. I couldn't. Tiny arms. A small, fragile body. My brain reflexively processed the only impossible conclusion.


Then, a face appeared before me. Long golden hair, bright blue eyes, a gentle smile.


It was the face of **my own birth mother**.


Memories came rushing in like a storm. The final battle. The Holy Hero with his blade of light. The last cry of a curse. And the end of everything.


I, **Kaiser von Zerath**, the Demon King feared by the entire world, was dead.


And now, I have been reborn—inside the body of my own son.


But the pain in my back is real. The scent of warm milk being spooned into my mouth is real. The soft sound of my mother's voice as she calls me "Leo" is also real.


My new name. The name I personally chose for my son when I was still alive as the Demon King. I wanted him to become the world's new hope. But instead, it's *me* who now lives inside him.


I don't even have hands to slap my forehead. No voice to protest. Only the uncontrollable wailing of a baby escapes my lips.


"Aww, is my little one tired?" my mother says, cradling me in her arms.


If I could speak, I'd say, *"Yeah, I'm tired. Tired because you once believed my words that I could bring peace through power."*


But all that comes out are tiny whimpers and drool.


I, the former leader of demon legions, a legendary sorcerer, the author of war doctrines studied by generals, am now nothing more than a baby drooling and peeing in its own diaper.


Still, despite how pathetic this all is, one thing is certain:


I never want to be the Demon King again. I'm sick of ambition, bloodshed, and a throne that brought nothing but loneliness.


> I will learn what it means to be human.


> I will learn how to be a good father… to myself.


Chapter 1 - I Woke Up As My Own Son