The Story in 3 Sentences
A selfless human death grants Roy a second life as a lowly demon egg, thrust into a brutal, unfamiliar hell where survival is the only law.
Armed with a god-like “Custom Made” system that trades souls for any creation he can sketch, he evolves from a vulnerable hatchling into a cunning apex predator, hopping between cinematic worlds to harvest power.
His journey culminates not in a return to humanity, but in the terrifying embrace of his demonic apotheosis, becoming a cosmic force of chaos and destruction that reshapes the very fabric of the Abyss.
Why It Stands Out
1. The Ultimate Power Fantasy, Unchained
Forget cultivation bottlenecks. This novel hands you a cosmic paintbrush and says, “Draw your godhood.” The “Custom Made Demon King System” is pure, unadulterated wish-fulfillment, letting Roy manifest Wolverine’s claws, demonic mechs, or Lovecraftian horrors on a whim, paid for in the currency of souls. It’s a sandbox where imagination is the only limit, turning every battle into a spectacle of creative, often absurd, power escalation that keeps readers hooked on the “what will he build next?” thrill.
2. A Demon Who Owns It
Roy doesn’t waste chapters angsting over his lost humanity. He sheds it like a snakeskin. This novel stands out by delivering on its premise: a true demon protagonist. He calculates, exploits, and devours without the hypocritical moral hand-wringing common in the genre. His transition from confused human to a being who finds ecstasy in soul consumption and thrives on spreading despair is a dark, refreshing arc that fulfills the fantasy of absolute, amoral power.
3. Multiversal Mayhem with a Nostalgic Twist
The summoning mechanic isn’t just a power source; it’s a gateway to pure fan-service. Roy doesn’t just visit other worlds; he crashes into iconic movie and game universes like Van Helsing and Heroes of Might and Magic, turning beloved settings into his personal hunting grounds. This meta-layer allows for hilarious, chaotic crossovers where he trolls heroes and exploits plot holes, offering a unique blend of action and nostalgic, fourth-wall-adjacent fun.
Characters That Leave a Mark
There’s Samael – the ancient, wrathful Demon King of the Abyss whose machinations kickstart the great wars, a primordial force of destruction whose shadow looms over Roy’s entire ascent.
You’ll meet Sparda, who defied his own kind by stealing sacred demonic knowledge, a powerful, enigmatic traitor-lord whose path crosses Roy’s in the heavenly realms, forcing uneasy alliances and high-stakes power plays.
And Lilith? They’re the one who represents the seductive, ancient power of the original demoness, a figure whose cryptic visions and immense power hint at deeper, older secrets within the Abyss that even Roy must reckon with.
The Flaws Fans Debate
The MC’s intelligence is wildly inconsistent, sometimes a strategic genius, other times a reckless idiot who treats the deadly Abyss like a theme park.
The system’s limitless potential is often squandered on trivial or poorly conceived creations, like making a pet for companionship instead of a weapon of mass destruction, frustrating readers who see wasted narrative opportunity.
The early chapters, particularly his first act in the Van Helsing world, feature morally jarring moments where the newly reborn demon kills innocents, alienating readers who expected a more nuanced anti-hero.
Must-Experience Arcs
Ch. 1–50: The Hatchling’s Gambit – Roy emerges from his egg, grasps the horrifying rules of his new demonic existence, and makes his first crude, soul-fueled modifications to survive the desolate wastes of the low Abyss.
Ch. 350–450: The Heavenly Contract – Roy, alongside the traitor-lord Sparda, navigates the treacherous politics and divine warfare of the Heavenly World, forging perilous power contracts and expanding his influence beyond the Abyss.
Ch. 650–701: The Chosen One of the Abyss – Roy sheds his final vestiges of limitation, fully embracing his role as a Chaos Demon and the Abyss’s ultimate weapon, culminating in a cataclysmic, reality-bending final war that redefines the cosmic order.
Killer Quotes
“Since becoming a demon, Roy noticed a distinct change in his eye structure. When he was human, he couldn’t see things like souls, but demons could.”
“It is in a demon’s nature to devour and play with souls. It refers to the pleasure and ecstasy brought about through devouring souls.”
“The Demon Realm here doesn’t make any sense to me! I don’t intend to be king here. This Demon Realm has been isolated from the rest.”
Cultural Impact
It sparked intense debates across forums about the definition of a “true demon” protagonist, with Roy becoming a benchmark for unapologetic villainy in the isekai genre.
The concept of “drawing your power” became a popular meme template, with fans photoshopping absurd weapons and creatures onto Roy, captioned with “Soul Cost: ???”.
Despite polarizing reviews, it amassed a cult following of millions of readers on WebNovel, celebrated for its sheer, unadulterated power fantasy and unique multiversal premise.
Final Verdict
Start Here If You Want:
A break from moralistic heroes and want to experience the raw, unfiltered power fantasy of being the ultimate villain.
Creative, over-the-top battles where the protagonist’s power is limited only by his imagination and the souls he can harvest.
A wild ride through familiar pop culture worlds, but from the terrifying, exploitative perspective of the invading demon.
Study If You Love:
Deconstructions of the isekai hero’s journey, where the protagonist fully embraces their monstrous new identity instead of fighting it.
Narratives that explore the philosophical implications of absolute power and the loss of humanity, even if done with a pulp-fiction flair.
The mechanics of world-building in a multiverse setting, where different fictional universes have tangible, exploitable rules and weaknesses.
Avoid If You Prefer:
Deep, consistent character development and strategic plotting over chaotic, system-driven power escalation.
Protagonists with a strong moral compass or who strive to be heroic, even in a dark world.
Stories that take their own lore and power systems with deadly seriousness, without moments of absurdity or fan-service.
